Category: Class 7

AP State Syllabus AP Board 7th Class Science Important Questions Chapter 13 Seed Dispersal

AP State Syllabus 7th Class Science Important Questions 13th Lesson Seed Dispersal

7th Class Science 13th Lesson Seed Dispersal Important Questions and Answers

Question 1.
How seeds are formed and give birth to new plants?
Answer:

1. We know that after fertilization ovary develops as fruit and ovules develop into seeds.
2. When the seeds germinate they give birth to new plants.

Question 2.
Why are seeds disperse to different distances. How do they disperse?
Answer:

1. We know that seed dispersal is necessary to grow tiny plants of the same species.
2. To avoid competition with the mother plant for air, water and minerals plants disperse their seeds to different distances.
3. But the process of dispersal varies from plant to plant.
4. Plants have special mechanism for seed dispersal.

Question 3.
Explain how does the dispersal of seeds through wind take place.
Answer:

1. The seeds of caltropis have light and hairy structure at one end.
2. They travel with wind and settle at a suitable place to germinate.
3. Seeds that are dispersed through air are usually light and are either very small or are light with wings on them or some hairy structures on them.
4. The seeds get adapted in such a way that they get carried away easily by wind.
5. Some seeds float in air, some propel to travel short distances.
   
6. In some plants like orchids seeds are minute with inflated covering.
7. In plants like maple, seeds have wing like outgrowths.
8. Cotton seeds have hairy structures.
9. These types of specialized structures, present in the seeds, will be helpful for dispersal by air.

Question 4.
Write a note on dispersal of seed by water.
Answer:

1. The seeds adapted to float on water are usually light. The outer covering of the seed has empty spaces filled with air and some are fibrous with air spaces that encloses the whole seed or fruit.
   Eg: Coconut.
2. The entire Coconut fruit floats on water and moves from one place to another.
   
3. When it reaches the ground it germinates.
4. That’s why we usually find coconut trees growing near sea shores.
   
5. Seeds that are heavy usually fall to the bottom of water sources and get carried by the flow of water. Ex: Seeds of Lotus.

Question 5.
Describe how animals help in the dispersal of seeds.
Answer:

1. Seeds are dispersed by animals in many ways.
   
2. In case of fleshy fruits, the fruit is eaten by animals while some dry fruits, with specialized structures like hooks, thorns, hairy parts, get stuck to the bodies of animals and get carried to distant places.
3. We find such seeds in some kind of grass plants.
4. We notice some kinds of fruits or seeds getting stuck to our clothes when we walk through fields and bushes.
5. They have hooks or thorns on them.

Question 6.
Explain how birds are also responsible for the dispersal of seeds.
Answer:

1. Some seeds are sticky and get stuck to the beaks of birds and in course of flight they fall down at distant places.
2. Often some birds carry seeds with their beaks. Some of them fall before they reach their nesting places.
3. We know some seeds have to pass through the guts of some birds before they germinate.
4. Birds like Bulbuls, Mynahs, Crows eat some fruits (Eg: Neem fruit) the outer fleshly part gets digested in the food canal and the seed coats of them become tender.
5. They are then dispersed to other places as bird droppings.

Question 7.
Why plants produced a large number of seeds?
Answer:

1. We have observed that fruits and vegetable plants that grow in our home garden produce a large number of seeds.
2. Some fruits grow in singly whereas some are in bunches.
3. Some fruits have a single seed in them and some have a large numebr of seeds.
4. All the seeds of a fruit should be able to germinate to produce new plants.
5. Actually this does not happen. If this happens we will see only same type of plants in large number in our surroundings.
6. All seeds don’t germinate. Some seeds never germinate to produce new plants. Some seeds germinate but plants die before maturation.
7. To overcome these problems plants produce a large number of seeds.

Question 8.
Collect some seeds like grass, poppy, bhendi, coconut etc. Try to collect different types of seeds like seeds with hair, thorns, big, small, light, heavy etc., and record the information in the given table :
Answer:

Question 9.
Observe the following figures. They are seeds with different shapes and structures.
Answer:

Question 10.
How do squirrels help in dispersal of seeds?
Answer:

1. It collects a lot of nuts and hides them underground before onset of winter.
2. It can hardly eat all of them and even forget where it has hidden its nuts!
3. Thus we have several nut trees at different places.

Question 11.
Do you agree with the fact that seeds are also travelling by aeroplanes, and ships ? Explain,
Answer:

1. Nowadays we see diffeernt kinds of fruits and vegetables around us.
2. Import and export of grains like wheat pulses, maize, paddy is a common practice through which many seeds get dispersed all over the world.
3. It is a wonder now that seeds also travel by aeroplanes and ships.

Question 12.
How many seeds a mustard plant does produce? How do you feel about it?
Answer:

1. A mustard plant produces more than 10,000 seeds in its lifetime.
2. If all the seeds germinate to grow into adult plants, think how many seeds would be produced. If this happens for a period of six years the entire globe will be covered with mustard plants.

Question 13.
Some animals eat fleshy fruits. How do they disperse the seeds of those fruits.
Answer:

1. Many fleshy fruits are meant to being eaten by animals.
2. The fleshy part of the fruit is eaten leaving the seeds uninjured.
3. Some seeds get dispersed through animal excretions

Question 14.
With the help of your teacher fill up the table given below.
Answer:
Observe the animals in your surroundings. Fill in the following table.

Question 15.
Describe how does the dispersal of seeds take place by the bursting of fruits that throw the seeds out.
Answer:

1. Many fruits enclose the seed in a capsule or pod.
   Upon drying the pod explodes releasing the seeds with great force in the surroundings.
2. We find such type of seeds in Bhendi, Mustard and seeds of Pea family.
   
3. Some seeds grow in capsules which when touched burst and uncoil with a force in such a way that they scatter the seeds all around.
4. The seeds of Balsam are dispersed in this manner.
5. We also noticed that some fruits explode when we sprinkle water on them and the seeds get dispersed.

Question 16.
Describe how the seeds of fruits tomato, cauliflower, guava, sugar cane transfered across the globe by people.
Answer:

1. We should know from where this tomato fruit has come from and that it is not native to India.
2. When European travellers came to trade in India, they left the seeds of vegetables like tomato, cauliflower, guava, pear on their return.
3. Similarly sugarcane which is native to India and is used worldwide for production of sugar, is a good example of how people transfer seeds/fruits from one place to another.

Question 17.
Use the information in the given table to answer the following questions.

Agents of seed dispersal	Name of the seed / fruit
by wind	Milk weed
by water	Coconut
by animals	Grass plants
by bird	Neem
by man	Mango

i) What is the agent of coconut seed dispersal?
ii) What is the dispersal agent ofneem seed?
iii) Name the seed which is dispersed by wind?
iv)What are the seeds dispersed by human intervention?
Answer:
i) Water
ii) Birds
iii) Caltropis
iv) Mango

SCERT AP 7th Class Science Study Material Pdf 2nd Lesson పదార్థాల స్వభావం Textbook Questions and Answers.

AP State Syllabus 7th Class Science 2nd Lesson Questions and Answers పదార్థాల స్వభావం

7th Class Science 2nd Lesson పదార్థాల స్వభావం Textbook Questions and Answers

Improve Your Learning (అభ్యసనాన్ని మెరుగుపరచుకుందాం)

I. ఖాళీలను పూరింపుము.

1. ఆమ్లం యొక్క రుచి. ………. (పులుపు)
2. ఒక పదార్థం pH విలువ 0. అయిన ఆ పదార్థం ……….. స్వభావాన్ని కలిగియుంటుంది. (క్షార)
3. చింతపండు రసంలో నీలి లిట్మస్ ………….. రంగులోకి మారును. (వరుపు)
4. ఆంటాసిడ్ ………………… స్వభావాన్ని కలిగియుంటాయి. (క్షార)
5. ఆమ్లము + క్షారము → …………….. + …….. (లవణము, నీరు)

II. సరైన జవాబు సూచించు అక్షరమును బ్రాకెట్ లో రాయండి.

1. ‘ఆమ్లాలలో పసుపు సూచిక రంగు
A) నీలం
B) ఎరుపు
C) ఊదా
D) రంగు మారదు
జవాబు:
D) రంగు మారదు

2. ఆమ్లానికి ఒక ఉదాహరణ
A) వెనిగర్
B) వంట సోడా
C) తినే సోడా
D) ఏదీకాదు
జవాబు:
A) వెనిగర్

3. సబ్బులోని ముఖ్యమైన అనుఘటకం ఏది?
A) ఆమ్లము
B) క్షారం
C) A & B
D) ఏదీకాదు
జవాబు:
B) క్షారం

4. నిమ్మరసానికి వంట సోడా కలిపితే ………. వాయువు విడుదలవుతుంది.
A) హైడ్రోజన్
B) ఆక్సీజన్
C) కార్బన్ డై ఆక్సైడ్
D) సల్ఫర్ డై ఆక్సైడ్
జవాబు:
A) హైడ్రోజన్

5. ఆమ్ల స్వభావం అధికంగా గల పొలానికి రైతులు ………. ని కలుపుతారు.
A) నిమ్మరసం
B) కాల్షియం ఆక్సైడ్
C) సోడియం క్లోరైడ్
D) సల్ఫర్
జవాబు:
B) కాల్షియం ఆక్సైడ్

III. జతపరచండి.

గ్రూపు – A	గ్రూపు – B
A) బ్యాటరీ	1) పదార్థాల నిల్వ
B) సబ్బు	2) కాల్షియం కార్బొనేట్
C) ఎసిటిక్ ఆమ్లం	3) సల్ఫ్యూరిక్ ఆమ్లం
D) మందారపువ్వు	4) కృత్రిమ సూచిక
E) గుడ్డు పెంకు	5) సోడియం హైడ్రాక్సైడ్
	6) సహజ సూచిక

జవాబు:

గ్రూపు – A	గ్రూపు – B
A) బ్యాటరీ	3) సల్ఫ్యూరిక్ ఆమ్లం
B) సబ్బు	5) సోడియం హైడ్రాక్సైడ్
C) ఎసిటిక్ ఆమ్లం	1) పదార్థాల నిల్వ
D) మందారపువ్వు	6) సహజ సూచిక
E) గుడ్డు పెంకు	2) కాల్షియం కార్బొనేట్

IV. ఈ క్రింది ప్రశ్నలకు జవాబులు రాయండి.

ప్రశ్న 1.
ఆమ్లాలు మరియు క్షారాల మధ్య తేడాలు రాయండి.
జవాబు:

ఆమ్లం	క్షారము
1) ఆమ్లాలు రుచికి పుల్లగా ఉంటాయి.	1) క్షారాలు రుచికి చేదుగా ఉంటాయి.
2) జారుడు స్వభావం కల్గి ఉండవు.	2) జారుడు స్వభావం కల్గి ఉంటాయి.
3) నీలి లిట్మస్ ను ఎర్రగా మార్చుతాయి.	3) ఎర్ర లిట్మసు నీలిగా మార్చుతాయి.
4) మిథైల్ ఆరంజ్ సూచికలో పసుపురంగుకు మారతాయి.	4) మిథైల్ ఆరంజ్ సూచికలో ఎరుపురంగుకు మారతాయి.
5) ఫినాఫ్తలిన్ సూచికను గులాబిరంగుకు మార్చుతాయి.	5) ఫినాఫ్తలిన్ సూచికలో రంగు మారదు.
6) మందార సూచికను గులాబిరంగుగా మార్చును.	6) మందార సూచికను ఆకుపచ్చగా మార్చును
7) వీటి pH విలువ 7 కన్నా తక్కువ.	7) వీటి pH విలువ 7 కన్న ఎక్కువ.
8) లోహాలతో చర్యపొంది H2 ను విడుదల చేయును.	8) క్షారాలు లోహాలతో చర్యపొంది హైడ్రోజన్ తో పాటు లవణాలను ఏర్పర్చుతాయి.

ప్రశ్న 2.
వివిధ రకాల ఆమ్ల క్షార సూచికలకు ఉదాహరణలివ్వండి.
జవాబు:
ఆమ్ల క్షారాలను గుర్తించటంలో సహాయపడే పదార్థాలను సూచికలు అంటారు. సూచికలు ప్రధానంగా నాలుగు రకాలు. అవి :
1) సహజ సూచికలు :
ప్రకృతిలో సహజంగా లభించే సూచికలను సహజ సూచికలు అంటారు. ఉదా : పసుపు, మందార.

2) కృత్రిమ సూచికలు :
ఖనిజ లవణాల నుండి తయారు చేసిన సూచికలను కృత్రిమ సూచికలు అంటారు.
ఉదా : ఫినాఫ్తలీన్, మిథైల్ ఆరంజ్

3) ఋణ సూచికలు :
ఆమ్ల లేదా క్షార పదార్థాలతో కలిసినపుడు కొన్ని సూచికలు వాసనను కల్గిస్తాయి.
ఉదా : ఉల్లిరసం, లవంగ నూనె

4) సార్వత్రిక సూచికలు : ఇవి వివిధ సూచికల మిశ్రమం వివిధ పదార్థాలతో వేరు వేరు రంగులను ఇస్తాయి.
ఉదా : బ్రోమో మిథైల్ బ్లూ, మిథైల్ రెడ్.

ప్రశ్న 3.
ఒక పదార్థం జారుగా మరియు చేదు రుచిని కలిగియుంది. ఇంకొక పదార్థం పులుపు రుచిని కలిగియుంది. ఆ రెండు పదార్ధాలను కలిపినప్పుడు ఏఏ పదార్థాలు ఏర్పడుతాయి?
జవాబు:

1. జారుగా చేదు రుచిని కలిగిన పదార్థం క్షారము.
2. రుచికి పుల్లగా ఉన్న పదార్థం ఆమ్లం.
3. ఆమ్లము మరియు క్షారము కలిసినపుడు తటస్థీకరణ చర్య జరుగును.
4. తటస్థీకరణ చర్యతో లవణము మరియు నీరు ఏర్పడతాయి.
   ఆమ్లము + క్షారము → లవణము + నీరు

ప్రశ్న 4.
సూచికలు లేకుండా అసిటిక్ ఆమ్లాన్ని నీవు ఎలా పరీక్షించగలవో ఊహించు.
జవాబు:

1. ఎసిటిక్ ఆమ్లం వెనిగర్ వాసనను కల్గి ఉండి రుచికి పుల్లగా ఉంటుంది. ఇది రంగులేని . ద్రవం.
2. పుల్లదనం కోసం దీనిని వంటకాలలో వాడతారు.
3. వాసనను మరియు రుచిని బట్టి ఎసిటిక్ ఆమ్లాన్ని గుర్తించవచ్చు.

ప్రశ్న 5.
అనిత వాళ్ళ అమ్మ మామిడి పచ్చడిని పింగాణి పాత్రలో నింపి, భద్రపరిచింది. ఇది చూసిన అనితకి చాలా సందేహాలు కలిగాయి. ఆ సందేహాలు ఏమై వుంటాయో రాయండి.
జవాబు:

1. పచ్చళ్ళను పింగాణి పాత్రలలోనే ఎందుకు నిల్వ చేస్తారు?
2. పింగాణి పాత్రలు దేనితో తయారుచేస్తారు?
3. పచ్చళ్ళను లోహపు పాత్రలో నిల్వ చేస్తే ఏమౌతుంది?
4. కొన్నిసార్లు పచ్చళ్ళు త్వరగా పాడౌతాయి ఎందుకు?
5. అన్ని పచ్చళ్ళలో నూనె ఉంటుందా?
6. పచ్చళ్ళకు అల్యూమినియం గరిట వాడవద్దు అంటారు ఎందుకు?

ప్రశ్న 6.
ఆమ్లం, క్షారం మరియు తటస్థ పదార్థములు చూపు pH స్కేలు పటాన్ని గీయండి.
జవాబు:

ప్రశ్న 7.
ఆమ్లము లోహములతో చర్య జరిపినప్పుడు హైడ్రోజన్ వాయువు వెలువడునని నిరూపించు ప్రయోగ పరికరాల ఏర్పాట్ల పటము గీయండి.
జవాబు:

ప్రశ్న 8.
ఎసిడిటీతో బాధపడుతున్న వారికి క్షారాలు చేయు సహాయాన్ని నీవెలా అభినందిస్తావు?
జవాబు:

1. జీర్ణాశయంలో అధిక ఆమ్లం వలన ఎసిడిటీ వస్తుంది.
2. దీనివలన పొట్టలో మంట, నొప్పి ఏర్పడతాయి.
3. క్షార పదార్ధమైన యాంటాసిడ్, ఈ ఆమ్లాన్ని తటస్థీకరణం చేస్తుంది.
4. యాంటాసిడ్లు ఉపశమనం కల్గిస్తాయి.
5. అజీర్తి, కడుపుమంటను నివారించటంలో యాంటాసిడ్లు అద్భుతంగా పనిచేస్తాయి.
6. యాంటాసిడ్ తీసుకొన్న తరువాత మంట తగ్గి ఎంతో హాయిగా అనిపిస్తుంది.
7. వైద్యశాస్త్రానికి, సైన్సుకు ధన్యవాదాలు తెలుపుకోవాలి.

చిటికెడు క్షారం కడుపు మంట మాయం చేసింది తటసీకరణం కలిగించింది ఉపశమనం

యాంటాసిడ్ అంటే ఆమ్ల కోపానికి కళ్ళెం పేరుకు క్షారమైనా తటస్థంతో పంచు ఆనందం

ప్రశ్న 9.
ఆమ్ల వర్షాల నివారణకు నీవు ఎటువంటి చర్యలను పాటిస్తావు?
జవాబు:
ఆమ్ల వర్షాలకు ప్రధాన కారణం వాయుకాలుష్యం. వాయుకాలుష్యం నివారించటం వలన ఆమ్ల వర్షాలను నివారించవచ్చు. వాయుకాలుష్య నివారణకు చర్యలు :

1. వాహనాల రద్దీ తగ్గించాలి.
2. శిలాజ ఇంధనాల వాడకాలు ఆపాలి.
3. ప్రత్యమ్నాయ ఇంధన వనరులను ప్రోత్సహించాలి.
4. బ్యాటరీ వాహనాలు పెంచాలి.
5. సౌరశక్తి వినియోగం పెంచాలి.
6. పరిశ్రమల పొగను శుభ్రపర్చాలి.
7. అడవులు పెంచాలి.
8. పరిసరాలలో పచ్చదనం పెంచాలి.

7th Class Science 2nd Lesson పదార్థాల స్వభావం InText Questions and Answers

7th Class Science Textbook Page No. 39

ప్రశ్న 1.
చింతపండు, నిమ్మరసం ఎందుకు పుల్లని రుచిని కల్గి ఉంటాయి?
జవాబు:
చింతపండు, నిమ్మరసం ఆమ్లాలను కల్గి ఉంటాయి. అందుచేత రుచికి పుల్లగా ఉంటాయి.

7th Class Science Textbook Page No. 55

ప్రశ్న 2.
క్షారాలలో లోహాలను వేస్తే ఏమి జరుగుతుంది?
జవాబు:
సోడియం హైడ్రాక్సైడ్ వంటి క్షారాలతో చర్యపొంది హైడ్రోజన్ వాయువును విడుదల చేస్తాయి.

ప్రశ్న 3.
పచ్చళ్ళను అల్యూమినియం రాగి, స్టీలు మొదలగు పాత్రలలో నిల్వ చేయరు. ఎందుకు?
జవాబు:

1. పచ్చళ్ళలో ఆమ్లాలు ఉంటాయి.
2. ఈ ఆమ్లాలు లోహపు పాత్రలలో చర్య జరిపి విషపదార్థాలను ఏర్పర్చుతాయి.
3. ఈ విష పదార్థాలు పచ్చళ్ళను పాడు చేయటమేగాక ఆరోగ్యానికి హానికరం.
4. అందుచేత పచ్చళ్ళను పింగాణి లేదా. గాజు పాత్రలలో నిల్వ చేస్తారు.

ప్రాజెక్ట్ పనులు

7th Class Science Textbook Page No. 69

ప్రశ్న 1.
వివిధ రకాల సూచికలను ఉపయోగించి వివిధ రకాల గ్రీటింగ్ కార్డులను తయారుచేయండి.
జవాబు:

ప్రశ్న 2.
బీట్ రూట్ తో సూచికను తయారుచేసి, కొన్ని ఆమ్లాలను, క్షారాలను దానితో పరీక్షించి నివేదిక రాయండి.
జవాబు:

1. మంచి రంగు ఉన్న బీట్ రూట్ ను ముక్కలుగా చేసి మిక్సీలో వేసి బీట్ రూట్ రసం తీసాను.
2. దీనిని జాగ్రత్తగా వడకట్టి పరీక్ష నాళికలోనికి తీసుకొన్నాను.
3. దీనిని వేరు వేరు ఆమ్లాలకు కలిపి పరీక్షించగా ఎటువంటి రంగుమార్పు కనపడలేదు.
4. బీట్ రూట్ సూచికను క్షార ద్రవాలకు కలిపి పరీక్షించినపుడు అవి ముదురు ఎరుపు రంగు నుండి పసుపు రంగుకు మారటం గమనించాను.
5. దీనిని బట్టి బీట్ రూట్ సూచిక క్షార ద్రవాలను గుర్తించటానికి తోడ్పడుతుందని నిర్ధారణ చేశాను.

ప్రశ్న 3.
వివిధ పంటపొలాలు సందర్శించి మట్టిని సేకరించి మట్టి పరీక్షలు నిర్వహించి నివేదికను తయారుచేయండి.
జవాబు:

1. నేను నా మిత్రులతో బృందముగా ఏర్పడి మా ఊరి పరిసర ప్రాంతాల నుండి పొలాలకు వెళ్ళి మట్టి నమూనాను సేకరించాము.
2. ప్రతి మట్టి నమూనా ఏ రైతు పొలం నుండి సేకరించబడినదో గమనించి నమోదు చేశాము.
3. ఆ పై మట్టిని నీటిలో నానబెట్టి లిట్మస్ పరీక్ష నిర్వహించాము.
4. దీని ద్వారా మట్టి రసాయన తత్వం తెలుసుకొని ఆ వివరాలను రైతులకు అందజేయటం జరిగింది.
5. క్షార స్వభావం ఉన్న నేలకు ఏ ఎరువులు వాడాలి. ఆమ్ల స్వభావం ఉన్న నేలకు ఏ ఎరువులు వాడాలో సూచించాము.
6. ప్రాజెక్టు వివరాలను జాగ్రత్తగా నమోదు చేసి భద్రపర్చాము.

రైతు పేరు	పొలం స్వభావము	సూచనలు
1. రామయ్య	ఆమ్ల స్వభావం	పొడిసున్నం చల్లాలి
2. వెంకటేశ్వర్లు	తేలికపాటి ఆమ్ల స్వభావం	నీటి నిల్వను పెంచాలి
3. శ్రీనివాసరావు	క్షారవంతం	పశువుల ఎరువు వాడాలి
4. కోటేశ్వరరావు	తేలికపాటి క్షారయుతం	కంపోస్ట్ ఎరువు వేయాలి

కృత్యాలు

కృత్యం -1

ప్రశ్న 1.
మీ వంటగదిలో వినియోగించే ఆహారపదార్థాల రుచి ఆధారంగా ఈ క్రింది పట్టిక నింపండి.

జవాబు:

పదార్థం	రుచి	ఆమ్లం/ఆమ్లం కాదు
1. టమాటా రసం	పులుపు	ఆమ్లం
2. పంచదార	తీపి	ఆమ్లం కాదు
3. పెరుగు	పులుపు	ఆమ్లం
4. పచ్చి మామిడి కాయ	పులుపు	ఆమ్లం
5. ఉప్పు	ఉప్పగా	ఆమ్లం కాదు
6. ఉసిరికాయ	పులుపు	ఆమ్లం
7. కమలా రసం	పులుపు	ఆమ్లం

కృత్యం -2

ప్రశ్న 2.
మీ అరచేతిలోకి సబ్బును తీసుకొని, కొద్దిగా నీటితో తడపండి. ఇప్పుడు మరొక అరచేతితో రుద్దండి.
రుద్దుతున్నప్పుడు ఎలా అనిపించింది?
జవాబు:
సబ్బు జారుడు స్వభావం తెలుస్తుంది.
ఇప్పుడు టూత్ పేస్ట్ తో ఈ కృత్యాన్ని చేయండి. మీకెలా అనిపిస్తుందో పరిశీలించండి.
టూత్ పేస్ట్ కూడా జారుడు స్వభావాన్ని కలిగి వుంటుంది.
ఈ పదార్థాలు జారుడు గుణం కలిగియుండే రసాయన పదార్థాలను కలిగి ఉంటాయి. ఈ రసాయనాలను క్షారాలు అంటారు. క్షారాలు జారుడు స్వభావాన్ని మరియు చేదు రుచిని కలిగి వుంటాయి.

కృత్యం – 3

ప్రశ్న 3.
ఎ) ఒక పాత్రలో ఒక చెంచా పసుపు పొడిని తీసుకోండి. దానికి కొద్దిగా నీటిని కలిపి ముద్దగా చేయండి. బ్లాటింగ్ కాగితాన్ని తీసుకుని, దానికి రెండువైపులా పసుపు ముద్దను పూయండి. (వడపోత కాగితం లేదా తెల్ల కాగితాన్ని కూడా ఉపయోగించవచ్చును) దానిని కొద్దిసేపు ఆరబెట్టండి. పూర్తిగా ఆరిన తర్వాత ఆ పసుపు కాగితాన్ని పట్టీలుగా కత్తిరించండి. ఇప్పుడు పసుపు కాగితపు పట్టీలు వినియోగించుటకు సిద్ధంగా యున్నవి.
ఈ పట్టీల రంగు ఏమిటి?
జవాబు:
ఇవి పసుపురంగులో ఉంటాయి.
పసుపు సూచికతో పరీక్ష

1. ఒక ప్లేటులో సబ్బు ద్రావణాన్ని తీసుకోండి. దానిలో ఒక పసుపు కాగితం పట్టీను ముంచండి. బయటకు తీసి పట్టీ రంగును పరిశీలించండి.
2. ఇదే కృత్యమును సున్నపు నీరు మరియు నిమ్మరసంతో కూడా చేయండి.

పట్టీల రంగులలో ఏవైనా మార్పులను పరిశీలించారా?
జవాబు:
మీ పరిశీలనలను కింది పట్టికలో నమోదు చేయండి.క్ర.సంఖ్య పదార్థం

పదార్థం	పరిశీలించిన రంగు మార్పు
1. సబ్బు ద్రావణం
2. సున్నపు నీరు
3. నిమ్మరసం

జవాబు:

పదార్థం	పరిశీలించిన రంగు మార్పు
1. సబ్బు ద్రావణం	ఎరుపు గోధుమ రంగు
2. సున్నపు నీరు	ఎరుపు గోధుమ రంగు
3. నిమ్మరసం	—

బి) మందార సూచికతో పరీక్ష
పరీక్ష నాళికలలో నిమ్మరసం, సోడా నీరు, సున్నపు ద్రావణం, గ్లూకోజ్ ద్రావణం, పంచదార ద్రావణం, సబ్బునీరు మొదలగు వాటిని తీసుకోండి. ప్రతి పరీక్ష నాళికలో తయారుచేసిన కొన్ని చుక్కల మందార సూచికను వేయండి. పదార్థాల రంగులలో మార్పులను పరిశీలించి పట్టికలో నమోదు చేయండి.

పదార్థం	పరిశీలించిన రంగు మార్పు
1. నిమ్మరసం
2. సోడానీరు
3. సున్నపు ద్రావణం
4. గ్లూకోజ్ ద్రావణం
5. పంచదార ద్రావణం
6. సబ్బు నీరు

జవాబు:

పదార్థం	పరిశీలించిన రంగు మార్పు
1. నిమ్మరసం	గులాబిరంగు
2. సోడానీరు	ఆకుపచ్చ
3. సున్నపు ద్రావణం	ఆకుపచ్చ
4. గ్లూకోజ్ ద్రావణం	—-
5. పంచదార ద్రావణం	—-
6. సబ్బు నీరు	ఆకుపచ్చ

ప్రయోగశాల కృత్యం -1

ప్రశ్న 4.
ఇవ్వబడిన ద్రావణాలు వివిధ సూచికలలో ఏ విధంగా మార్పు చెందుతాయో పరిశీలించండి.
కింది ద్రావణాలను పరీక్ష నాళికలలో తీసుకోండి. వీటిని సూచికలతో పరిశీలించండి. 1) ఎర్ర లిట్మస్ 2) నీలి లిట్మస్ 3) మిథైల్ ఆరెంజ్ 4) ఫినాఫ్తలీన్

జవాబు:

నీలి లిట్మస్ ఆమ్లాలలో ఎరుపు రంగులోకి మారుతుంది. ఎర్ర లిట్మస్ క్షారాలలో నీలిరంగులోకి మారుతుంది. మిథైల్ ఆరెంజ్ ఆమ్లాలో ఎరుపు రంగులోకి, క్షారాలలో పసుపు రంగులోకి మారుతంది.

ఫినాఫ్తలీన్ సూచిక క్షారాలలో గులాబీ(పింక్) రంగులోకి మారుతుంది. ఆమ్లాలలో ఫినాఫ్తలీన్ రంగులో మార్పురాదు.

స్వచ్ఛమైన నీటిలో పై ఏ సూచిక రంగులోనూ మార్పురాదు. ఎందుకంటే నీరు తటస్థ పదార్థం.

కృత్యం – 4

ప్రశ్న 5.
సజల హైడ్రోక్లోరికామ్లం, వెనిగర్, నీరు, సోడియం హైడ్రాక్సైడ్, అమ్మోనియం హైడ్రాక్సైడ్ లను పరీక్ష నాళికలలో తీసుకోండి. ప్రతి పరీక్ష నాళికలో రెండు చుక్కల సార్వత్రిక సూచికను కలుపండి.
పరీక్ష నాళికలలోని అన్ని ద్రావణాలు వివిధ రంగులలోకి మారడాన్ని మీరు పరిశీలించవచ్చును. ఇప్పుడు సార్వత్రిక సూచిక సీసాపై ఇవ్వబడిన రంగుల పట్టీతో ఈ ద్రావణాల రంగులను పోల్చండి.
ఆమ్లాలు మరియు క్షారాల బలాలను అవి చూపిన రంగుల ఆధారంగా వర్గీకరించి, పట్టికలో రాయుము.

జవాబు:

ప్రయోగశాల కృత్యం-2

ప్రశ్న 6.
ఆమ్లాలు లోహాలతో చర్య జరిపి హైడ్రోజన్ వాయువును విడుదల చేస్తాయి అని ఎలా నిరూపిస్తావు?
(లేదా)
ప్రయోగశాలలో హైడ్రోజన్ వాయువు తయారీ విధానం తెలపండి.
జవాబు:
ఉద్దేశ్యం : ఆమ్లం లోహంతో చర్య జరిపి హైడ్రోజన్ వాయువును విడుదల చేస్తుంది.

ఏమి కావాలి :
శంభాకార గాజు పాత్ర (కోనికల్ ఫ్లాస్క్), హైడ్రోక్లోరిక్ ఆమ్లం, జింకుముక్కలు, మండుతున్న పుల్ల.

ఎలా చేయాలి :
ఒక శంఖాకార గాజు పాత్రను తీసుకొని, దానిలో 5 గ్రా. జింకు ముక్కలను వేయండి. దానిలో సజల హైడ్రోక్లోరిక్ ఆమ్లాన్ని పోయండి. ఏమి జరుగుతుందో గమనించండి.

ఒక మండుతున్న పుల్లని ప్లాస్క్ మూతి వద్ద ఉంచండి. పుల్ల నున్న మంట టప్ అనే శబ్దంతో ఆరిపోతుంది. ఇది హైడ్రోజన్ వాయువును నిర్ధారించు పరీక్ష, హైడ్రోక్లోరిక్ ఆమ్లం జింకుతో చర్య జరిపి హైడ్రోజన్ వాయువును విడుదల చేస్తుంది. ఈ చర్యను క్రింది విధంగా పద సమీకరణంలో రాయ వచ్చును.

హైడ్రోక్లోరిక్ ఆమ్లం + జింకు – జింక్ క్లోరైడ్ + హైడ్రోజన్

నేర్చుకున్నది ఏమిటి :
కావున, ఆమ్లాలు లోహాలతో చర్య జరిపి హైడ్రోజన్ వాయువును విడుదల చేస్తాయని నిర్ధారించవచ్చును.

కృత్యం – 5

ప్రశ్న 7.
ప్రయోగశాల కృత్యం – 2ను ఈసారి సజల హైడ్రోక్లోరిక్ ఆమ్లానికి బదులు సోడియం హైడ్రాక్సైడు ఉపయోగించండి. వెలువడిన వాయువును మండుతున్న పుల్లతో పరీక్షించండి.
ఏ వాయువు వెలువడింది?
జవాబు:
సోడియం హైడ్రాక్సైడ్ లోహాలతో చర్య జరిపి హైడ్రోజన్ వాయువును విడుదల చేస్తుంది. కానీ, అన్ని క్షారాలు అన్ని లోహాలతో చర్య జరపవు.

కృత్యం – 6

ప్రశ్న 8.
కొన్ని గుడ్డు పెంకు ముక్కలను ఒక పరీక్ష నాళికలో తీసుకోండి. దానిలో సజల హైడ్రోక్లోరిక్ ఆమ్లమును గుడ్డు పెంకును మునిగేంత వరకు పోయండి. పరీక్ష నాళికలో జరిగే మార్పులను పరిశీలించండి. గుడ్డు పెంకు కాల్షియం కార్బొనేట్ తో నిర్మితమవుతుంది.
మీరు ఏమైన వాయువులు విడుదలవ్వడం పరిశీలించారా?
జవాబు:
పరీక్ష నాళిక మూతి వద్దకు ఒక మండుతున్న పుల్లను తీసుకురండి.

ఏమి జరిగినది?
జవాబు:
మండుతున్న పుల్ల ఆరిపోతుంది. కాబట్టి ఆ వాయువు కార్బన్ డై ఆక్సైడ్. ఆమ్లము కాల్షియం కార్బొనేట్ తో చర్య జరపడం వలన ఇది ఉత్పన్నమైనది.

కృత్యం – 7

ప్రశ్న 9.
తటస్థీకరణ చర్యను ప్రయోగశాలలో ఎలా నిరూపిస్తావు?
జవాబు:
ఉద్దేశం : తటస్థీకరణ చర్యను నిరూపించుట

పరికరాలు : కోనికల్ ఫ్లాస్క్, డ్రాపర్

రసాయనాలు : సోడియం హైడ్రాక్సైడ్, హైడ్రోక్లోరిక్ ఆమ్లం, ఫినాఫ్తలీన్

విధానం :

1. ఒక కోనికల్ ఫ్లాలో సోడియం హైడ్రాక్సైడ్ ద్రావణం తీసుకొని దానికి కొన్ని చుక్కలు ఫినాఫ్తలీన్ ‘ కలపాలి. అప్పుడు అది గులాబీరంగుకు మారుతుంది.
2. దీనికి సజల హైడ్రోక్లోరిక్ ఆమ్లాన్ని చుక్కలుగా కలుపుతూ డ్రాపి కలియబెట్టండి.

పరిశీలన :
కాసేపటికి ఫ్లాలోని ద్రవం గులాబీరంగును కోల్పోతుంది.

వివరణ :
దీనికి కారణం సజల హైడ్రోక్లోరిక్ ఆమ్లం, సోడియం హైడ్రాక్సైడ్ తో చర్య పొంది తటస్థీకరణం చేయటమే.

హైడ్రోక్లోరిక్ ఆమ్లం + సోడియం హైడ్రాక్సైడ్ → నీరు + సోడియం క్లోరైడ్
ఆమ్లం క్షారంతో చర్యపొంది లవణము, నీటిని ఏర్పర్చే ఈ ప్రక్రియను తటస్థీకరణ అంటారు.

కృత్యం – 8

ప్రశ్న 10.
పంట పొలం యొక్క మట్టి స్వభావాన్ని ఎలా పరీక్షిస్తారు?
జవాబు:
మీ దగ్గరలో గల పంటపొలాన్ని సందర్శించండి. పొలం నుండి మట్టి నమూనాను సేకరించండి. ఒక బీకరులో గాలిలో ఆరిన 10 గ్రా. సేకరించిన మట్టిని వేయండి. దానికి అరలీటరు నీటిని కలిపి బాగా కలియబెట్టండి. ద్రావణాన్ని వడకట్టండి. ఇప్పుడు వడకట్టిన ద్రావణాన్ని యూనివర్సల్ సూచిక లేదా pH పేపరుతో పరీక్షించండి. ఈ పరీక్ష ద్వారా మట్టి స్వభావం తెలుస్తుంది.

Andhra Pradesh SCERT AP State Board Syllabus 7th Class Science Study Material Guide Pdf free download, AP Board 7th Class Science Textbook Solutions in English Medium and Telugu Medium are part of AP Board 7th Class Textbook Solutions.

Students can also go through AP Board 7th Class Science Notes to understand and remember the concepts easily. Students can also read AP 7th Class Science Important Questions for exam preparation.

AP State Syllabus 7th Class Science Guide Study Material Pdf Free Download

AP 7th Class Science Study Material Pdf | 7th Class Science Textbook State Syllabus Pdf Download

AP 7th Class Science Study Material Pdf English Medium New Syllabus

SCERT 7th Class Science Solutions Sem 1

• 1st Lesson Food for Health
• 2nd Lesson Nature of Substances
• 3rd Lesson Nutrition in Organisms
• 4th Lesson Respiration and Circulation
• 5th Lesson Motion and Time
• 6th Lesson Electricity

7th Class Science Study Material Pdf Sem 2

• 7th Lesson Reproduction in Plants
• 8th Lesson Wonders of Light
• 9th Lesson Heat, Temperature and Climate
• 10th Lesson Changes Around Us
• 11th Lesson Fibres and Fabrics
• 12th Lesson Soil and Water

AP 7th Class Science Guide Telugu Medium

SCERT Class 7 Science Solutions Sem 1

• 1st Lesson ఆహారంతో ఆరోగ్యం
• 2nd Lesson పదార్థాల స్వభావం
• 3rd Lesson జీవులలో పోషణ
• 4th Lesson శ్వాసక్రియ – ప్రసరణ
• 5th Lesson చలనం – కాలం
• 6th Lesson విద్యుత్

7th Class Science Guide Sem 2

• 7th Lesson మొక్కలలో ప్రత్యుత్పత్తి
• 8th Lesson కాంతితో అద్భుతాలు
• 9th Lesson ఉష్ణం, ఉష్ణోగ్రత మరియు శీతోష్ణస్థితి
• 10th Lesson మన చుట్టూ జరిగే మార్పులు
• 11th Lesson దారాలు – దుస్తులు
• 12th Lesson నేల మరియు నీరు

AP 7th Class Science Study Material Pdf English Medium (Old Syllabus)

Telangana SCERT Class 7 Science Solutions | AP State 7th Class Science Textbook Pdf

• Chapter 1 Food Components
• Chapter 2 Acids and Bases
• Chapter 3 Animal Fibre
• Chapter 4 Motion and Time
• Chapter 5 Temperature and Its Measurement
• Chapter 6 Weather and Climate
• Chapter 7 Electricity – Current and Its Effect
• Chapter 8 Air, Winds and Cyclones
• Chapter 9 Reflection of Light
• Chapter 10 Nutrition in Plants
• Chapter 11 Respiration in Organisms
• Chapter 12 Reproduction in Plants
• Chapter 13 Seed Dispersal
• Chapter 14 Water – Too Little To Waste
• Chapter 15 Soil: Our Life
• Chapter 16 Forest: Our Life
• Chapter 17 Changes Around Us

AP State Syllabus AP Board 7th Class Science Important Questions Chapter 17 Changes Around Us

AP State Syllabus 7th Class Science Important Questions 17th Lesson Changes Around Us

7th Class Science 17th Lesson Changes Around Us Important Questions and Answers

Question 1.
What are periodic changes?
Answer:

S.No.	Name of the Change
1.	Change of day and night
2.	Withering of leaves
3.	Rising of the pole star
4.	Change of Seasons
5.	Change of Greenery in the fields of cultivation
6.	Changes in lengths of shadows
7.	Appearance of Full Moon

1. If we observe that every change mentioned is the table repeats after some period of time.
2. Such changes are known as periodic changes.
3. The events which repeat at regular intervals of time are called periodic events.

Question 2.
Mention some physical changes you observe in your daily life.
Answer:

1. In our daily life we observe many changes.
2. In the changes like melting of ice, solidification of ghee or coconut oil in winter etc., there is a change in state of the substance.
3. In certain processes like filling balloons with air and pumping of cycle tubes etc., we notice change in shape.
4. These are all physical changes. On these changes no new substance is formed.

Question 3.
Explain what are physical and chemical changes. Give examples.
Answer:
Physical change: When the material undergoes a change in shape, size, colour or state, it is called a physical change.
Eg: Heating ice, filling air into Balloons
Chemical change: When a material undergoes a change in shape and size and a new material is formed, then we call it a chemical change.
Eg:

1. Burning of crackers
2. Change of milk into curd
3. Burning a piece of wood.

Question 4.
Some changes are given in the table. Write possible changes you notice for each case and put (✓) in the appropriate column.
Answer:

1. In the above activity we notice that only in some examples like burning of paper, burning of crackers, change of milk to curd, boiling of egg, etc., a new substance is formed.
2. But in other examples of changes, we notice a change in state or colour or size or shape etc but the substance remains the same and no new substance is formed.

Question 5.
In the above table which changes do you consider physical changes or chemical changes?
Answer:

1. When a material undergoes a change in shape, size, colour, or state, it is called a physical change.
2. So I consider the following as physical changes.
   Heating a coloured candle, Heating ice, Heating water, Melting of Gold ornaments, Filling of air into Balloons, Cutting a piece of wood, Drying of clothes in sunlight, Drying of wet coconut, change is the cut apple; Change in the mouth due to pan chewing.
3. When a material undergoes a change in its composition, it is called a chemical
   change. In a chemical change, a new substance is formed.
4. So I consider the following as chemical changes. Burning of Newspaper, Burning of crackers, change of milk to curd, Boiling egg.

Question 6.
What is rust and rusting? Why does iron rust? What type of change is this?
Answer:

1. When iron nails, iron gates, iron benches or pieces of iron are left is the open ground for a long time, we find a brown layer on the surface of iron articles.
2. This is called ‘rust’, and the process of forming this layer is called rusting.
3. When iron is exposed to air for a long time, the Oxygen present in air reacts with it in the presence of moist air and forms a new substance called iron oxide as rust on iron articles.
4. This process is known as rusting.
   Iron + Oxygen (from air) + Water → rust (Iron oxide).
5. As a new substance is formed in this change, we call it a chemical change.

Question 7.
What is Galvanisation? Explain its importance.
Answer:

1. Some articles made up of iron, don’t get rusted even they are exposed to air.
2. To prevent iron articles from coming into contact with oxygen in air or water or both, we deposit a layer of a metal like Chromium or Zinc on them.
3. This process of depositing a layer of zinc or Chromium on Iron is called Galvanisation.
4. Generally we use Zinc for such type of coatings.
5. We find in our house that water pipe lines are without rust on them.
6. If we observe carefully, we notice that there is some metallic coating on these pipes to prevent rusting.
7. They do not get rusted even after a long time since they are galvanized.
8. The process of depositing one metal on another metal is called galvanisation.

Question 8.
What happens when you burn camphor?
Answer:

1. Initially Camphor changes into liquid and then evaporates into air.
2. It is also considered to be a chemical change.

Question 9.
What happens when you put a small quantity of Camphor in a dish and place it in the open air?
Answer:

1. Take a small quantity of Camphor in a dish and place it in the open air.
2. Observe it after some time. Its quantity reduces and we sense the smell of it.
3. It happens because the camphor gets evaporated. Since it has strong smell, it is used to keep insects and flies away. It is also used in medicines.

Question 10.
Describe what changes occur in a chemical change.
Answer:

1. In a chemical change, the material undergoes a change in its composition and a new substance is formed.
2. Heat, light or any other radiation may be given out or absorbed.
3. Loud sound may be produced.
4. A change in smell may take place or a new smell may be produced.
5. A colour change may take place.
6. A change in the state may occur. All chemical changes do not have all the 2 to 6 traits mentioned above.

Question 11.
How do you make crystallization of urea?
Answer:

1. Take some water in a test tube and add urea to it. Heat the test tube till all the urea dissolves.
2. Add more urea to it. Keep on adding to it until no more urea can be dissolved in it.
3. Let the solution cool down for sometime.
4. Observe the test tube after about half an hour.
5. We get large size crystals of urea.

Question 12.
What is crystallization? How do you make crystallization of copper sulphate?
Answer:
Crystallization (Definition): The process of separating a soluble solid from the solution by heating or evaporating is called crystallization.
Crystallization of copper sulphate:

1. Take some hot, saturated solution of Copper sulphate in a test tube.
2. Pour some of it in an evaporating dish.
3. Allow the solution to cool quickly.
4. Observe with a magnifying glass, the size, colour and shape of the crystals formed.

Question 13.
Think about the following changes and decide whether they are physical or chemical changes. Write the type of change and reasons for that in the table.
Answer:

Question 14.
Do copper articles get rust? When rusting becomes faster? What change is this?
Answer:

1. When Copper utensils are exposed to air we find a greenish coat on them.
2. This greenish coat is formed when Copper reacts with Oxygen and Carbon dioxide present in the air.
3. This coat also protects Copper from getting further corroded. It is also an example of rusting.
4. Rusting becomes faster when there is more humidity in the air.
5. Rusting is a chemical change.

Question 15.
How can you say that rusting is a chemical change? What factors are favourable for speed rusting?
Answer:

1. In case when the metal is changed to its oxide, that is rusting a new substance is formed.
2. Hence rusting is a Chemical Change.
3. The speed of rusting depends on the amount of moisture available to it for a long time.
4. That is more the humidity in air, the faster is the rusting of iron.

Question 16.
What are the methods you suggest to prevent the rusting of iron?
Answer:

1. The problem of rusting of iron and other metal articles is common experience in almost every home.
2. It spoils beautiful articles and makes them look ugly.
3. The following are some of the ways to prevent the rusting of iron.
   a) Do not allow the iron articles to come in direct contact with Oxygen in the air, water or both.
   b) Apply a coat of paint or grease on an iron article.

Question 17.
Do all the materials get rusted or react with oxygen in the air?
Answer:

1. Observe Gold and Silver, we wear them in the form of ornaments.
2. Even if they get exposed to air for a long time, they do not change colour or get rusted.
3. It means that they are resistant to corrosion which is the reason why we use them in making ornaments.

Question 18.
What changes do you notice when few pieces of ice in a beaker are heated? What do you mean by a physical change ?
Answer:

1. Take few pieces of ice in a beaker and heat them as shown in the following figure.
   
2. We notice that ice slowly melts and becomes water and on further heating.
3. If we reduce the temperature, the water vapour changes back to water and when the temperature is further reduced it changes to ice.
4. In the above activity we notice the change of the state of ice to water and to vapour but the substance, water, remains the same.
5. Changes of this type where no new substance is formed are known as physical changes.
6. When a material undergoes a change in shape, size, color or state it is called a Physical Change.
7. Generally, no new substance is formed in a physical change.

Question 19.
What changes do you observe when some material is burning? What do you mean by a chemical change?
Answer:

1. Take a piece of wood, a piece of paper and a ball of cotton. Burn them and observe the changes.
   
2. Record your observations in the following Table.
   
3. In the above activity we notice that when a piece of wood, paper, and cotton are burnt a new material is formed.
4. This is black in colour and in powder form which is different from the original material.
5. We also notice change in shape and size of new material.
6. This type of change that leads to form a new substance is known as Chemical change.

Question 20.
What happens when magnesium ribbon is burnt in air? What type of substance is formed when it is dissolved in water?
Answer:

1. Take a small piece of Magnesium ribbon. Burn it on a flame of candle.
2. We will find brilliant white dazzling light leaving a powdery substance behind.
3. When Magnesium burns in the presence of Oxygen, it forms Magnesium Oxide in the form of powder ash, which is a new substance.
4. Thus there is a change in the composition.
5. Magnesium + Oxygen → Magnesium Oxide.
6. Collect the ash and mix it with a small quantity of water and dissolve it. Another new substance is formed.
7. Magnesium Oxide + Water → Magnesium Hydroxide
8. Test the dissolved mixture with blue and red litmus papers to decide whether it is a acid or a base.
9. We notice that the litmus paper turns blue.
10. This means that magnesium hydroxide is basic in nature.
11. As all these are new substances all these changes are chemical changes.

Question 21.
What happens if you put an iron nail in copper sulphate solution? Describe how do you perform this activity.
Answer:

1. Take a glass tumbler half – filled with water and add a teaspoonful of Copper sulphate to it.
2. Now add a few drops of Sulphuric Acid to the Copper Sulphate solution.
3. Take some sample solution of it in another beaker and keep it aside.
   
4. Add an Iron nail to the solution in the first beaker and keep it undisturbed for half an hour.
5. Compare the colour of the solution in which iron nail is dropped to that of sample solution kept aside.
6. We notice that the blue coloured solution changes into green colour and a brown coloured deposit is seen on the iron nail.
7. The change in colour of the solution is due to the formation of Iron Sulphate, a new substance.
8. The brown deposit on the Iron nail is copper, another new substance.
9. Copper Sulphate (Blue) + Iron → Iron Sulphate (green) + Copper (brown deposit).
10. This is a chemical change.

Question 22.
Describe how do you perform the activity to observe the reaction of vinegar with baking soda.
Answer:

1. First set up the apparatus has shown in Fig.
   
2. Take a teaspoon of vinegar (acetic acid) in a test tube and add a pinch of baking soda (Sodium bicarbonate) to it.
3. You observe bubbles coming out with a hissing sound. Pass this gas through freshly prepared Limewater (Calcium Hydroxide).
4. Limewater changes to milky white showing that the gas sent into the test tube is Carbon dioxide.
5. Vinegar + Baking Soda → Carbon dioxide + other substance.
6. Carbon dioxide + Lime Water → Calcium Carbonate + Water
7. In these reactions, the new substances like Carbon dioxide and Calcium Carbonate are formed. Hence it is a chemical change.
8. When a material undergoes a change in its composition it is called a chemical change.

Question 23.
How do you produce large size of sugar crystals? What type of change is it?
Answer:

1. Take a big size test tube. Fill half if it with water. Add some sugar to it and stir it.
2. Keep adding sugar and stirring until saturation is attained. Then heat this sugar solution and add some more sugar to it while stirring
3. Continue adding sugar till no more sugar can be dissolved in it.
   
4. Now filter the solution and allow it cool for half an hour.
5. We notice formation of large size crystals of sugar at the bottom of the beaker. Thus sugar the small granules of sugar added changed into large size sugar crystals.
6. This is a physical change.

Question 24.
What do you observe on the cut pieces of fruits and vegetables? Why do they change their colour?
Answer:

1. Take an apple, brinjal, a potato, a tomato, a cucumber, a banana; cut each into small pieces; place them in separate plates and expose them to open air for sometime.
   
2. We notice a brown colour in some of these pieces.
3. Some fruits and vegetables, when cut, react with Oxygen in the air.
4. This makes them to get a brown layer on the surface.

Question 25.
What do you do to prevent browning of cut vegetables and fruits.
Answer:

1. Cold water prevents the outer surface of the potato and brinjal from colouring.
2. Small quantities of acids like vinegar or lemon juice in water will also prevent browning of vegetables.
   
3. We can also rub the surface of the cut fruits with juices of citrus fruits like lemon to avoid their browning.
4. The layer of lemon juice reduces the reaction on the surface of the fruit.
5. Ascorbic acid (vitamin C) can also be used to prevent browning.

Question 26.
Look at the experiment given below which was already conducted in your laboratory. Answer the following.

a) Which chemical was used in this experiment?
b) What is the change of colour you observed, after putting the iron nail into the solution?
Answer:
a) Copper Sulphate solution (CuSO₄).
b) The solution turns into green colour.

AP State Syllabus AP Board 7th Class Science Important Questions Chapter 12 Reproduction in Plants

AP State Syllabus 7th Class Science Important Questions 12th Lesson Reproduction in Plants

7th Class Science 12th Lesson Reproduction in Plants Important Questions and Answers

Question 1.
Describe the flowers that are classified on the basis of parts present in them.
Answer:
Flowers are classified as:
a) Complete flower
b) Incomplete flower
c) Unisexual flower and
d) Bisexual flower on the basis of parts present in them.
a) Complete flower:
A flower that has four or more whorls – at least one each of calyx (sepals), corolla (petals), Androecium (stamens) and Gynoecium (pistil) is called a Complete flower.

Eg: Datura, ipomea, hibiscus.

b) Incomplete flower:
A flower in which any of these four whorls is missing is an Incomplete flower.

Eg: Cucumber, bottlegourd, papaya.

c) Unisexual flower:
A flower which has either stamens (androecium) or pistil (gynoecium) is called unisexual flower.

Eg: Cucumber, bottle gourd, bitter gourd etc.,

d) Bisexual flower :
A flower that has both stamens and pistil (androecium and gynoecium).

Eg: Datura, hibiscus, ipomoea, is called bisexual.

Question 2.
What is pollination? What happens to pollinated and non-pollinated flowers?
Answer:

1. The process of pollen grains reaching the stigma from anther is known as pollination.
2. After one week if we observe both pollinated and non – pollinated flowers. We find polinated flowers develop into fruits where as non – pollinated flowers do not.

Question 3.
What are the agents that help, in pollination? Describe how it takes place by taking an example.
Answer:

1. Air, water, animals, insects, humans act as agents of pollination.
2. They carry pollen grains from anther to the stigma.
3. Insects like butterflies suck nectar from flowers.
4. At that time pollen grains of that flower stick to the legs of the butterfly.
5. When the butterfly goes to another flower for nectar, the pollen grain that have stuck to it’s legs fall on that flower.

Question 4.
What is fertilization? What happens after fertilization?
Answer:

1. Fertilization: Fusion of units of male and female parts to form a structure called as zygote is called fertilization.
2. After fertilization seed develops from the ovule and the ovary usually develops into a fruit.
3. The entire process of fertilization and formation of zygote is known as Sexual reproduction.
4. For the formation of a seed sexual reproduction is essential.
5. The seed thus formed are dispersed to different places by agents like air, water, birds and animals and by human beings as well.
6. These seeds grow into new plants under favorable conditions.

Question 5.
What is sexual reproduction?
Answer:
Production of baby plants or offsprings from the zygote is called sexual reproduction.

Question 6.
What is vegetative reproduction? Write an example for such reproduction.
Answer:
Vegetative reproduction: Production of new plants from vegetative parts of a plant i.e. root, stem and leaf is known as vegetative reproduction.
Example:

1. Potato has a number of small depressions on its surface.
2. These are known as eyes. Cut the potato into pieces such that there is an eye in each piece.
3. Remove the eyes from some of these pieces. Fill two cups with soil.
4. Plant the piece with eyes in one cup and label the cup as ‘with eyes” and those without eyes in another cup named as “Without eyes”.
5. Water both cups daily and observe potato plants sprout in the cup where pieces with eyes are kept.

Question 7.
How does reproduction take place in Bryophyllum?
Answer:

1. See the picture of the plant called Bryophyllum.
   
2. We can see baby plants on the edge of the leaves.
3. We can say that the Bryophyllum plant reproduces through its leaves.

Question 8.
Name some plants which can reproduce when a small branch of them is cut and planted in the soil.
Answer:
In our garden we grow plants like rose, hibiscus, and jasmine by cutting a small branch and planting them in the soil.

Question 9.
Do all flowers have four parts?
Answer:
The student can do this with the help of the teacher. Collect as many flowers from your surroundings as you can. See that you have at least a type of melon or gourd flower as well. Now observe different parts in each flower. Record your observations in the table given below.

Question 10.
How do you identify the sexual parts of a flower?
Answer:

1. Now take a stamen (androecium) from the datura flower, tap the stamen gently on a slide.
2. We can see some grains fallen on the slide.
   
3. Put a drop of water and observe these grains under the microscope.
4. These grains are called pollen grains. Collect pollen grains from other flowers and observe under the microscope as well.
5. Take the pistil of a datura flower as it is big enough to observe the internal parts.
6. Cut the sections of the ovary of pistil as shown in figures a and b.
   
   With the help of hand lens study the internal parts.
7. We see some small ball like structures called “ovules” can be seen arranged in different chambers.

Question 11.
How do you notice which flower part develops into fruit?
Answer:

1. Collect a pistil and fruit from datura plant. Cut the transverse section of both ovary of pistil and fruit.
2. Observe the internal structure of both the section cuttings with the help of a handlens.
   
3. Collect pistil and fruit of cucumber, bhendi (Ladies finger), cotton and beans and do the above activity.
4. Observe the similarities between the ovary and fruit of the same species.
5. It is reasonable to conclude that an ovary develops into a fruit while the ovules develop into seeds. The seeds further produce new plants.

Question 12.
How do you observe ‘Self Pollination ‘and ‘Cross PollinationWhat role is played by male flower?
Answer:

1. Observe a bottle-gourd plant in a garden. It has unisexual flowers i.e. male and female flowers separately.
2. Select 10 female buds of bottle guard, cover with a polythene bag loosely tying the bag on a stalk.
   
3. Make some tiny holes in the bag with the help of a pin.
4. Two days later observe the buds blooming. (Now collect the pollen grains from a male flower of the Bottlegourd plant).
5. Pluck the stamens of male flower and shake to collect pollen grain in a sheet of paper. Twisting cotton wool over the tip of a match stick prepares a brush.
6. Now uncover five of the ten female flowers. Apply the pollen grain on to the stigma of these flowers with the brush.
7. The pollen grains stick to the stigma.
8. Cover the flowers again with polythene bag. Remove all male flowers from the plant.
9. So that no pollen grain reaches the remaining female flowers.
10. By this experiment we come to know that significant role is played by male flower in the formation of fruit.
11. If transfer of pollen grains take place within the flower it is known as Self Pollination. Transfer of pollen grain from anther of one flower to stigma of another flower of same species is called Cross Pollination.

Question 13.
What happens to the pollen grain after pollination? What is fertilization?
Answer:

1. Take two slides. Put 2-3 drops of water on them. Add some sugar grains to water on one side.
   
2. Now put some pollen grains of Hibiscus flower on both the slides. After one hour observe under microscope. We find pollen grains germinate on the slide containing sugar grain.
3. There are some substances present on the stigma which promote the germination of the pollen grains.
4. During germination a tube grows from the pollen grain.
5. This tube ultimately reaches the ovary through the style with the male part.
6. This male part fuses with the female part in the ovule of the ovary.
7. Fusion of units of male and female parts to form a structure called as zygote is called Fertilization.

Question 14.
What is budding? How do you demonstrate it?
Answer:
1) Yeasts grow with the help of a small bulb like outgrowth which increases in size and • breaks off from the parent plant to live independently.
2) This process of reproduction is called budding.

Demonstration:

1. Take some water in a glass tumbler. Mix a tablespoon of sugar and half spoon of yeast powder you get in the market, in the glass tumbler.
2. Cover the glass and leave it undisturbed for a day.
   
3. On the next day place a drop of the solution on a slide and cover it with a cover slip and examine it under a microscope.
4. We can see budding yeast cells as shown in the figure, (they look like water bubbles growing new ones on them).

Question 15.
What is mould? How can you do an activity to show it?
Answer:

1. Take a slice of bread cover it with a vessel and leave it undisturbed for two or three days.
2. Thereafter you will find the slice covered with grey coloured fungus called bread mould.
   
3. Let it stand for three or four days. The whole growth appears like a black powder like matter.
4. Transfer this powder with a thin stick on a fresh slice of moist bread.
5. Observe what happens after every day and note your observation.
6. The black powdery portion of bread mould contains several spores.

Question 16.
What is thalamus in a flower?
Answer:
Let us hold a Dhatura flower by its stalk. This stalk is green in colour and has a slightly swollen head. This is called thalamus. It is the seat on which the parts of a flower are present.

Question 17.
Explain what are calyx and sepals in a flower.
Answer:

1. Now let us observe the part that comes just above the thalamus.
2. There is a green tube like structure called Calyx.
   
3. The edges on the part towards the petals have thin leaf like structures called sepals.
4. The lower ends of-sepals are fused to form the tube like structure.

Question 18.
Write about corolla.
Answer:

1. If we remove the tube of fused sepals in the flower carefully we see
2. There is a funnel shaped corolla. This is formed of fused petals.

Question 19.
What is the male part or Androecium of a flower?
Answer:

1. After removing the petals we can see soft elongated structures attached to these petals.
2. They are called stamens.
3. There is a bulb like structure at the top of each stamen that is called pollen sac or anther.
4. Just below it a fine whitish thread like structure called filament attaches the anther to the petal (in Datura).
5. So stamen has an elongated filarftent and a bulb like pollen sac.
6. Stamens of the flowers are together called the male part or androecium.

Question 20.
What is Gynoecium? How do you find it is a flower?
Answer:

1. As we remove petals, right on the thalamus is seated a bulb like structure called ovary.
2. Just above it a fine tube like structure called style goes up ending in a somewhat flat bead like structure called stigma.
3. This whole structure from ovary to stigma is the pistil or one female reproductive part.
4. All the parts present on the pistil together called as gynoecium.

Question 21.
What do you see in sun flower?
Answer:

1. Sun flower looks like a single flower.
2. But is actually a bunch of flowers.
3. The small flowers in the bunch are called ‘florets’.
4. The florets in the centre are called disc florets.
5. The florets along the rim are called ray flowers.

Question 22.
How are flowers classified on the basis of number of parts present in them?
Answer:
Flowers are classified as
a) Complete flower b) Incomplete flower c) Unisexual flower d) Bisexual flower

Question 23.
What is Penicillin? Who discovered it?
Answer:
Alexander Fleming a Scottish scientist, discovered that a certain kind of mould (Penicillium) produces a substance, named after the mould, called Penicillin, which can destroy many kinds of disease causing bacteria. Penicillin came to be know as an antibiotic and saved the lives of many soldiers in World War – II.

Question 24.
Observe various types of stamens of different flowers.
Answer:

Question 25.
Observe the different types of pistil drawn below.
Answer:

Question 26.
Write the differences between pollination and fertilization.
Answer:

Pollination	Fertilization
1) It is the transfer of pollen grains from anther to stigma.	1) It is the fusion of a male and female gametes.
2) External agents like water, wind and insect are needed.	2) It does not require external agent.

Question 27.
Draw a flow chart for Reproduction in plants.
Answer:

Question 28.
What is asexual production- How do you appreciate this?
Answer:

1. Reproduction of plants from all such parts other than the flower is asexual reproduction.
2. It is a great thing in nature because reproduction in plants is not confined only to sexual reproduction.
3. By way of such processes, we could get good vegetation.

Question 29.
Write the importance of flowers. Name some of them.
Answer:

1. Flowers are usually the most attractive part of any plant.
2. Flowers are so attractive and colourful. Because they attract insects, human beings, etc. to get cross – pollination.
3. Reproduction is possible through flowers also.
4. Datura, Chinarose (Hibiscus), Cucumebr, Bottlegourd, Tridax, Sun flower, Ipomea etc.

Question 30.
The student is advised to complete the table given below taking the help of the teacher.
Answer:

Question 31.
How are the pesticides causing destruction to our beautiful nature?
Answer:

1. Birds and insects are the natural agents for pollination.
2. Nowadays farmers use pesticides to control pests on crops.
3. The enormous use of pesticides kills insects also.
4. It effects pollination.
5. Crop yield become reduced particularly in sun flower crop.
6. The rate of pollination is reduced because of lack of insects in the fields.
7. Think! How we destroy our beautiful nature.

Question 32.
We often find that some plants grow from their cuttings or some other parts. Can you name some such plants?
Answer:

S.No.	Name of the Plant	Plant part from which new plant produced
1.	Potato	New plants grow from eyes in the tuber
2.	Onion	New plants grow from bulbs
3.	Sugarcane	Stem grows roots at the nodes
4.	Bryophyllum	New plants grow from buds on the leaf.

Question 33.
Look at the picture.

1. Identify the parts A, B, C.
2. Name the type of reproduction seen here.
3. Which part is converted into seed?
4. What is meant by Fertilization?

Answer:

1. A – Pollen grain; B – Pollen tube; C – Ovary
2. Sexual reproduction.
3. Ovules develop into seeds.
4. Fusion of units of male and female parts (Pollen grain and Ovules) to form a structure called zygote is called fertilization.

SCERT AP 7th Class Science Study Material Pdf 1st Lesson ఆహారంతో ఆరోగ్యం Textbook Questions and Answers.

AP State Syllabus 7th Class Science 1st Lesson Questions and Answers ఆహారంతో ఆరోగ్యం

7th Class Science 1st Lesson ఆహారంతో ఆరోగ్యం Textbook Questions and Answers

Improve Your Learning (అభ్యసనాన్ని మెరుగుపరచుకుందాం)

I. ఖాళీలను పూరింపుము.

1. తృణధాన్యాలు మరియు చిరుధాన్యాలలో …………….. సమృద్ధిగా ఉంటాయి. (పిండిపదార్థం)
2. పప్పుధాన్యాలలో ……………….. పుష్కలంగా ఉన్నాయి. (ప్రోటీన్స్)
3. మలబద్దకాన్ని నివారించటానికి ఎక్కువ ………… తీసుకోవాలి. (పీచుపదార్థం)
4. విటమిన్ డి లోపం వల్ల ………………. వ్యాధి కలుగుతుంది. (రికెట్స్)
5. విటమిన్ సి లోపం ………………….. వ్యా ధికి కారణమవుతుంది. (స్కర్వి)

II. సరైన జవాబు సూచించు అక్షరమును బ్రాకెట్లో రాయండి.

1. రమణ నువ్వుగింజలను నలిపి, కాగితంపై రుద్దాడు. అతను రుద్దిన చోట కాగితం అర్ధపారదర్శకంగా మారింది. ఆ గింజలలో ఏ పదార్థం ఉన్నది?
A) పిండిపదార్థాలు
B) మాంసకృత్తులు
C) క్రొవ్వులు
D) నీరు
జవాబు:
C) క్రొవ్వులు

2. ఇది లోపిస్తే రక్తహీనత వ్యాధి కలుగుతుంది.
A) జింక్
B) ఇనుము
C) విటమిన్ ఎ
D) కాల్షియం
జవాబు:
B) ఇనుము

3. ఇది లోపించడం వలన మనకు దృష్టి లోపాలు కలుగుతాయి.
A) విటమిన్-ఎ
B) విటమిన్-బి
C) విటమిన్-సి
D) విటమిన్-డి
జవాబు:
A) విటమిన్-ఎ

VI. జతపరచండి.

గ్రూపు – A	గ్రూపు – B
A) రేచీకటి	1) పిండిపదార్థాలు
B) శక్తినిచ్చే ఆహారం	2) ఇనుము
C) శరీర నిర్మాణ పోషకాలు	3) విటమిన్-ఎ
D) సంరక్షక ఆహారం	4) మాంసకృత్తులు
E) రక్తహీనత	5) ఖనిజ లవణాలు, విటమిన్లు
	6) సోడియం

జవాబు:

గ్రూపు – A	గ్రూపు – B
A) రేచీకటి	3) విటమిన్-ఎ
B) శక్తినిచ్చే ఆహారం	1) పిండిపదార్థాలు
C) శరీర నిర్మాణ పోషకాలు	4) మాంసకృత్తులు
D) సంరక్షక ఆహారం	5) ఖనిజ లవణాలు, విటమిన్లు
E) రక్తహీనత	2) ఇనుము

IV. ఈ క్రింది ప్రశ్నలకు జవాబులు రాయండి.

ప్రశ్న 1.
ఆహారంలోని అంశాలను పేర్కొనండి.
జవాబు:

1. ఆహారంలో ప్రధానంగా 1) పిండిపదార్థాలు 2) మాంసకృత్తులు 3) క్రొవ్వులు 4) ఖనిజ లవణాలు 5) విటమిన్లు ఉంటాయి.
2. వీటిలో పిండిపదార్థాలు, మాంసకృత్తులు, కొవ్వులు అధికపరిమాణంలో అవసరం. కావున వీటిని స్థూల పోషకాలు అంటారు.
3. ఖనిజ లవణాలు మరియు విటమిన్లు తక్కువ పరిమాణంలో అవసరం కాబట్టి వీటిని సూక్ష్మపోషకాలు అంటారు.
4. ఇవన్ని ఉన్న ఆహారాన్ని సంతులిత ఆహారం అంటారు.

ప్రశ్న 2.
మధ్యాహ్న భోజన సమయంలో నీవు తీసుకున్న ఆహార జాబితాను తయారుచేయండి. ప్రతి ఆహార పదార్థంలోని అంశాలను రాయండి.
జవాబు:

నేను తీసుకొన్న ఆహారం	అందులోని అంశాలు
1. అన్నము	పిండిపదార్థం
2. చపాతి	పిండిపదార్థం
3. గుడు	ప్రొటీన్స్
4. చికెన్	ప్రొటీన్స్
5. నూనె	క్రొవ్వు
6. ఉప్పు	ఖనిజలవణం

ప్రశ్న 3.
మన ఆహారంలో నీటి యొక్క పాత్ర ఏమిటి?
జవాబు:
మన రక్తంలో నీరు కూడా ఒక భాగం. కానీ నీటిలో ఏ పోషకాలూ ఉండవు. కనుక ఇది పోషకంగా గుర్తించబడదు. మన శరీర బరువులో దాదాపు మూడింట రెండు వంతులు నీరు ఉంటుంది. ఇది శరీర ఉష్ణోగ్రతను క్రమపరుస్తుంది. శరీరం నుండి కొన్ని వ్యర్థాలను మూత్రం మరియు చెమట రూపంలో విసర్జించడానికి ఇది సహాయపడుతుంది. అనేక జీవక్రియలకు నీరు అవసరం. జీర్ణనాళం ద్వారా ఆహారం కదిలివెళ్ళడానికి నీరు సహాయపడుతుంది. ఇది ఆహారాన్ని జీర్ణం చేయడానికి కూడా సహాయపడుతుంది.

ప్రశ్న 4.
పోషకాహార లోపం వల్ల కలిగే న్యూనత వ్యాధుల గురించి తెలుసుకోవటానికి పోషకాహార నిపుణుడిని నీవు ఏమి ప్రశ్నలు అడుగుతావు?
జవాబు:
ప్రశ్నలు:

1. పోషకాహార లోపం అనగానేమి?
2. పోషకాహార లోప కారణాలు ఏమిటి?
3. పోషకాహార లోపంలో రకాలు ఉన్నాయా?
4. పోషకాహార లోపం అధిగమించటానికి ఏమి చేయాలి?
5. పోషకాహార లోప ప్రభావం ఏమిటి?
6. పిల్లలలో పోషకాహార లోపం ఉంటుందా?

ప్రశ్న 5.
మన ఆహారంలో పీచుపదార్థాలను చేర్చకపోతే ఏమి జరుగుతుంది?
జవాబు:

1. పీచు పదార్థం ప్రధానంగా మొక్కల ఆహారం నుండి లభిస్తుంది.
2. కూరగాయలు, ఆకుకూరలు, దుంపలు, పండ్లు, మొలకలు మొదలగునవి పీచుపదార్థాల యొక్క ప్రధాన వనరులు.
3. చిలకడదుంప, బత్తాయి వంటి ఆహారపదార్థాలలో పీచుపదార్థం ఎక్కువ.
4. ఆహారంలో పీచుపదార్థం లేకపోతే మలబద్దకం ఏర్పడుతుంది.

ప్రశ్న 6.
గంజిలో పిండిపదార్థాలు ఉన్నాయని మేరీ ఎక్కడో చదివింది. దాన్ని నిర్ధారించటానికి ఆమె చేయవలసిన పరీక్షను వివరించండి.
జవాబు:
ఉద్దేశం : గంజిలో పిండి పదార్థాల ఉనికిని నిర్ధారించుట.

ఏం కావాలి :
1) సజల అయోడిన్ ద్రావణము (కొన్ని అయోడిన్ స్పటికాలను లేత గోధుమ రంగులోకి వచ్చే వరకు నీటిలో కరిగించండి) 2) గంజి 3) పాత్ర 4) డ్రాపరు

ఎలా చేయాలి :
ఒక పాత్రలో గంజి తీసుకోవాలి. దానికి 2 లేదా 3 చుక్కల సజల అయొడిన్ ద్రావణాన్ని కలపండి. అయొడిన్ వేసిన తర్వాత రంగులో మార్పును గమనించండి. పిండి పదార్థం ఉంటే అది నీలం నలుపు రంగులోకి మారుతుంది.

ఏం చూశావు :
గంజి నీలి – నలుపు రంగులోకి మారింది.

ఏం నేర్చుకున్నావు :
గంజిలో పిండి పదార్థం ఉంది.

ప్రశ్న 7.
ఇవ్వబడిన ఆహారంలో ప్రోటీన్ల ఉనికిని నీవు ఎలా పరీక్షిస్తావు? (ప్రయోగశాల కృత్యం-2)
జవాబు:
ఉద్దేశం : గుడ్డు తెల్లసొనలో మాంసకృత్తుల నిర్ధారణ పరీక్ష.

ఏం కావాలి :

1. 2% కాపర్ సల్ఫేట్ ద్రావణం (2 గ్రా. కాపర్ సల్ఫేటను 100 మి.లీ. నీటిలో కలపాలి)
2. 10% సోడియం హైడ్రాక్సైడ్ ద్రావణం (10 గ్రా. సోడియం హైడ్రాక్సైడు 100 మి.లీ. నీటిలో కలపాలి)
3. గుడ్డు
4. పరీక్షనాళికలు
5. రెండు బీకరులు
6. డ్రాపర్.

ఎలా చేయాలి :
పరీక్ష నాళికలో పది చుక్కల గుడ్డు తెల్లసొన తీసుకోవాలి. రెండు చుక్కల కాపర్ సల్ఫేటు మరియు పది చుక్కల సోడియం హైడ్రాక్సైడ్ ద్రావణాలను కలపాలి. బాగా కదిలించి, పరీక్షనాళికను కొన్ని నిమిషాలు స్టాండ్ లో ఉంచాలి. పదార్థం యొక్క రంగులో వచ్చే మార్పును గమనించండి. పదార్ధం ఊదారంగులోకి మారితే, అందులో మాంసకృత్తులు ఉన్నట్లు,

ఏం చూశావు :
గుడ్డులో తెల్లసొన ఊదారంగులోనికి మారింది.

ఏం నేర్చుకున్నావు :
గుడ్డులోని తెల్లసొనలో మాంసకృత్తులు ఉన్నాయి.

ప్రశ్న 8.
మన శరీరానికి ఆవశ్యకమైన పరిమాణాన్ని దృష్టిలో ఉంచుకొని పోషకాలను ఒక పిరమిడ్ గా బొమ్మ గీయండి.
జవాబు:

ప్రశ్న 9.
మన ఆరోగ్యాన్ని సక్రమంగా ఉంచడంలో ఆకుకూరల పాత్రను అభినందించండి.
జవాబు:

1. ఆకుకూరలు మన శరీరానికి అవసరమైన వివిధ రకాల ఖనిజ లవణాలను కల్గి ఉంటాయి.
2. ఇవి శరీరం సక్రమంగా ఎదగటానికి మనం ఆరోగ్యంగా ఉండటానికి ఉపయోగపడతాయి.
3. ఆకుకూరలలోని ఖనిజ లవణాలను రక్షక పోషకాలు అంటారు. ఇవి శరీరాన్ని వ్యాధుల నుండి రక్షిస్తాయి.
4. ఆకుకూరలు ప్రధానంగా విటమిన్-ఎ కల్గి ఉండి కంటి ఆరోగ్యానికి తోడ్పడతాయి.
5. ఆకుకూరలలోని పీచుపదార్థం మలబద్దకాన్ని నివారిస్తుంది.
6. ఆకుకూరలు సులువుగా జీర్ణమై, జీర్ణవ్యవస్థ ఆరోగ్యాన్ని కాపాడతాయి.
7. అందుకే ఆకుకూరలు వాడదాం, ఆరోగ్యంగా ఉందాం.
8. పచ్చని ఆకుకూరలు – ఆరోగ్యానికి మెట్లు.

ప్రశ్న 10.
సంతులిత ఆహారం అంటే ఏమిటి?నీ రోజువారి భోజనం సంతులిత ఆహారంగా ఉండటానికి, ఏయే పదార్థాలను చేరుస్తావు?
జవాబు:

1. అన్ని పోషకాలను అవసరమైన పరిమాణంలో కలిగి ఉన్న ఆహారాన్ని సంతులిత ఆహారం అంటారు.
2. ఇది మన శరీరం సమర్థవంతంగా పనిచేయటానికి అవసరమైన పోషకాలను అందిస్తుంది.
3. సంతులిత ఆహారంలో పిండి పదార్థం ప్రోటీన్స్, క్రొవ్వులు, విటమిన్లు, ఖనిజ లవణాలు సరైన మోతాదులో ఉండాలి.
4. పిండిపదార్థం కోసం నేను అన్నం, చపాతిని; ప్రొటీన్స్ కోసం పాలు, గుడ్లు, మాంసాన్ని; క్రొవ్వు కొరకు నూనె, నెయ్యిని; విటమిన్లు కోసం, కాయగూరలు, పండ్లను నా ఆహారంలో చేర్చుకుంటాను.

7th Class Science 1st Lesson ఆహారంతో ఆరోగ్యం InText Questions and Answers

7th Class Science Textbook Page No.3

ప్రశ్న 1.
మధ్యాహ్న భోజనంలో మీకు వడ్డించే ఆహార పదార్థాలను పేర్కొనండి.
జవాబు:
మధ్యాహ్న భోజనంలో అన్నం, సాంబారు, గుడ్డు, చిక్కి వంటి పదార్థాలు రోజువారి మెను ప్రకారం వడ్డిస్తున్నారు.

ప్రశ్న 2.
బడి పిల్లలకు మధ్యాహ్న భోజనం అందించటానికి కారణం ఏమిటి?
జవాబు:
పిల్లలందరు ఆరోగ్యంగా పౌష్టికాహార లోపం లేకుండా ఉండాలని మధ్యాహ్న భోజనం అందిస్తున్నారు.

7th Class Science Textbook Page No. 5

ప్రశ్న 3.
మధ్యాహ్న భోజనంలో అన్ని రోజులు ఒకే మెను ఉంటుందా?
జవాబు:
లేదు. మధ్యాహ్న భోజనం మెను వారాన్ని బట్టి మారిపోతూ ఉంటుంది.

ప్రశ్న 4.
మధ్యాహ్న భోజనంలో ఎందుకు వివిధ రకాల ఆహార పదార్థాలు వడ్డిస్తారు?
జవాబు:
వివిధ రకాల ఆహార పదార్థాలను తీసుకొన్నప్పుడే మన శరీరానికి అవసరమైన అన్ని రకాల పోషకాలు అందుతాయి.

ప్రశ్న 5.
చిక్కిలో ఏయే పోషకాలు ఉంటాయి?
జవాబు:
చిక్కిలో ప్రధానంగా ప్రొటీన్స్, నూనె పదార్థం, ఐరన్ వంటి పోషకాలు ఉంటాయి.

ప్రశ్న 6.
గుడ్డులో ఉండే పోషకాలు ఏమిటి?
జవాబు:
గుడ్డులో ప్రొటీన్స్, క్రొవ్వులతో పాటు, విటమిన్స్, మినరల్స్ వంటి అన్నిరకాల పోషకాలు లభిస్తున్నాయి.

ప్రశ్న 7.
మనం తీసుకొనే ఆహారపదార్థంలోని అంశాలు ఏమిటి?
జవాబు:
మనం తీసుకొనే ఆహారపదార్ధంలో

1. పిండిపదార్థాలు
2. మాంసకృత్తులు
3. క్రొవ్వులు
4. ఖనిజ లవణాలు
5. విటమిన్లు ఉంటాయి.

ప్రశ్న 8.
స్థూల పోషకాలు, సూక్ష్మ పోషకాలు అనగానేమి?
జవాబు:
శరీరానికి ఎక్కువ మోతాదులో అవసరమయ్యే పోషకాలను స్థూల పోషకాలు అంటారు.
ఉదా : పిండిపదార్థం, మాంసకృత్తులు.

శరీరానికి తక్కువ పరిమాణంలో అవసరమయ్యే పోషకాలను ‘సూక్ష్మపోషకాలు’ అంటారు.
ఉదా : విటమిన్లు, లవణాలు.

7th Class Science Textbook Page No. 7

ప్రశ్న 9.
మ్యాచ్ విరామ సమయంలో క్రికెట్ ఆటగాళ్ళు పానీయాలు తాగే సన్నివేశం మీకు బాగా తెలుసు. వారు పానీయాలు ఎందుకు తీసుకొంటారు?
జవాబు:

1. మనం అలసిపోయినపుడు సాధారణ స్థితికి రావడానికి మనకు శక్తి కావాలి.
2. క్రికెట్ మ్యాచ్ ఆడటానికి ఆటగాళ్ళకు నిరంతరం శక్తి కావాలి.
3. ఆటగాళ్ళు తీసుకొనే పానీయాలలో గ్లూకోజ్ ఉంటుంది.
4. ఇది ఆటగాళ్ళకు తక్షణ శక్తి ఇస్తుంది. అందువలన విరామసమయంలో ఆటగాళ్ళు డ్రింక్స్ సేవిస్తారు.

7th Class Science Textbook Page: No. 15

ప్రశ్న 10.
రక్తహీనతకు కారణాలు ఏమిటి?
జవాబు:
ఐరన్ లోపం వలన రక్తహీనత కలుగుతుంది.

ప్రశ్న 11.
దృష్టి సమస్యలకు కారణం ఏమిటి?
జవాబు:
విటమిన్-ఎ లోపం వలన దృష్టి సమస్యలు కలుగుతాయి.

7th Class Science Textbook Page No. 17

ప్రశ్న 12.
రేచీకటి నివారించటానికి ఎటువంటి ఆహారం తీసుకోవాలి?
జవాబు:
విటమిన్ – ఎ వలన రేచీకటి నివారించవచ్చు.

ప్రశ్న 13.
విటమిన్-కె లోపిస్తే ఏమవుతుంది?
జవాబు:
విటమిన్-కె లోపిస్తే రక్తం త్వరగా గడ్డకట్టదు.

ప్రశ్న 14.
చంటి పిల్లలకు కొద్ది సమయం ఉదయం పూట ఎండతగిలేలా ఉంచుతారు. ఎందుకు?
జవాబు:
సూర్యరశ్మి సోకటం వలన శరీరంలో విటమిన్-డి తయారౌతుంది.

ప్రశ్న 15.
కోవిడ్-19 పరిస్థితులలో విటమిన్-సి తీసుకోవాలని సూచిస్తారు. ఎందుకు?
జవాబు:
విటమిన్-సి శరీరంలో వ్యాధి నిరోధకతను పెంచుతుంది.

7th Class Science Textbook Page No. 23

ప్రశ్న 16.
పోషకాలలో ఏవైనా కొన్ని పోషకాలు లేని ఆహారం తీసుకొంటే ఏమి జరుగుతుంది?
జవాబు:
పోషకాలు లేని ఆహారం తీసుకొంటే పోషకాహార లోపం ఏర్పడుతుంది. దీని వలన శరీరం అనారోగ్యం పాలవుతుంది.

7th Class Science Textbook Page No. 27

ప్రశ్న 17.
మనం ఏ ఆహార పదార్థాలను ఎక్కువ మొత్తంలో తీసుకోవాలి?
జవాబు:
మనం పిండిపదార్థాలను ఎక్కువ మోతాదులో తీసుకోవాలి.

ప్రశ్న 18.
ఏ ఆహారపదార్థాలను తక్కువ మొత్తంలో తీసుకోవాలి?
జవాబు:
క్రొవ్వులు లేదా నూనెలను తక్కువ మొత్తంలో తీసుకోవాలి.

ఆలోచించండి – ప్రతిస్పందించండి

7th Class Science Textbook Page No. 21

ప్రశ్న 1.
పండ్లను, కూరగాయలను తొక్కతో సహా తినడం మంచిదా ? చర్చించండి.
జవాబు:

1. పండ్లు, కూరగాయల తొక్కలలో పీచుపదార్థం, విటమిన్స్ అధికంగా ఉంటాయి.
2. వీటిని తీసి తినటం వలన పోషకాలను కోల్పోతాము.
3. కాని ఇటీవల కాలంలో రసాయన సాగు వలన పండ్ల తొక్కలు రసాయన పూరితమైనాయి.
4. వీటిని తీసి తినటమే శ్రేయస్కరంగా ఉంది.

7th Class Science Textbook Page No. 25

ప్రశ్న 2.
శిశువులు కొన్ని నెలలపాటు పాలను మాత్రమే తీసుకొని ఎలా పెరగగల్గుతున్నారు?
జవాబు:

1. పాలు శిశువుల ప్రధాన ఆహారం.
2. పాలలో పుష్కలంగా ప్రొటీన్స్ మరియు లిపిడ్స్ ఉంటాయి.
3. ప్రొటీన్స్ శరీర నిర్మాణానికి లిపిడ్ శక్తిని ఇస్తాయి.
4. పాలు ఒక సంపూర్ణ ఆహారం. అందువలన శిశువులు కేవలం పాలతోనే కొన్ని నెలలు పాటు పెరగగల్గుతున్నారు.

ప్రాజెక్ట్ పనులు

7th Class Science Textbook Page No. 35

ప్రశ్న 1.
పన్నెండేళ్ళ పిల్లలకి సమతుల్య ఆహారం అందించటానికి డైట్ చార్టు తయారుచేయండి. డైట్ చార్ట్ లో ఖరీదైనవి కాని, మీ ప్రాంతంలో సాధారణంగా లభించే ఆహారపదార్థాలు ఉండాలి.
జవాబు:
1) అన్నము 2) చపాతీ 3) గుడ్లు 4) మాంసం 5) చేప 6) నెయ్యి 7) పాలు 8) పెరుగు 9) కాయలు 10) చిక్కి 11) బెల్లం 12) వేరుశనగలు 13) పిండి వంటకాలు 14) పాయసం 15) స్వీట్లు

ప్రశ్న 2.
మీ తల్లిదండ్రులతో చర్చించి, సంప్రదాయ ఆహారపదార్థాలు – వాటి పోషక విలువలు తెలియజేసే ఒక పట్టిక తయారుచేయండి.
జవాబు:

సాంప్రదాయ ఆహారపదార్థం	పోషకాలు	కాలరీ
1. పూరి	100 గ్రా.	150 గ్రా.
2. రోటి	100 గ్రా.	90 గ్రా.
3. లస్సి (sweet)	200 మి.గ్రా.	90 గ్రా.
4. మిక్స్డ్ వెజిటబుల్స్	150 గ్రా.	298 గ్రా.
5. గులా జామ్	2	331 గ్రా.
6. చికెన్ కర్రీ	150 గ్రా.	85 గ్రా.

కృత్యాలు

కృత్యం -1

ప్రశ్న 1.
సిసిరిత, తన తమ్ముడి కోసం, అంగన్‌వాడీ వర్కర్ తెచ్చిన బాలామృతం ప్యాకెట్ పై గల ఈ క్రింది పోషకాల సమాచారాన్ని చూసింది. వాటిని అధ్యయనం చేసి, ఈ కింది ప్రశ్నలకు జవాబులు వ్రాయండి. (పదాలు ఇంగ్లీషులో ఉంటాయి. వాటి తెలుగు పదాల కోసం నిఘంటువును చూడండి లేక మీ ఉపాధ్యాయుని సహకారం తీసుకోండి).

ఏయే అంశాలు ఎక్కువ పరిమాణంలో ఉన్నాయి? (గ్రాములలో)
జవాబు:
పిండిపదార్థాలు, మాంసకృత్తులు, కొవ్వులు అధిక పరిమాణంలో ఉన్నాయి.

ఏయే అంశాలు తక్కువ పరిమాణంలో ఉన్నాయి? (మి.గ్రా.లలో లేదా తక్కువ)
జవాబు:
విటమిన్లు, ఖనిజలవణాలు తక్కువ పరిమాణంలో ఉన్నాయి.

ప్రయోగశాల కృత్యం

ప్రశ్న 2.
బంగాళదుంపలో పిండిపదార్థాల ఉనికిని ఎలా నిర్ధారిస్తావు?
జవాబు:
ఉద్దేశం : బంగాళాదుంపలో పిండిపదార్థాల ఉనికిని నిర్ధారించుట.

ఏం కావాలి :

1. సజల అయోడిన్ ద్రావణము (కొన్ని అయోడిన్ స్ఫటికాలను లేత గోధుమ రంగులోకి వచ్చే వరకు నీటిలో కరిగించండి)
2. బంగాళాదుంప ముక్క
3. చాకు
4. పళ్ళెము
5. డ్రాపరు

ఎలా చేయాలి :
ఒక పళ్ళెం మీద బంగాళాదుంప ముక్క తీసుకోండి. బంగాళాదుంప ముక్కపై రెండు చుక్కల అయోడిన్ ద్రావణం వేయండి. అయోడిన్ వేసిన చోట రంగులో మార్పును గమనించండి. పిండిపదార్థం ఉంటే అది నీలం-నలుపు రంగు లోకి మారుతుంది.

ఏం చూశావు :
బంగాళదుంపలోని భాగం నీలం – నలుపు రంగులోకి మారింది.

ఏం నేర్చుకున్నావు :
బంగాళదుంపలో పిండి పదార్థం ఉంది. ఈ కింది ఆహార పదార్థములలో పిండి పదార్థముల ఉనికిని పరీక్షించి, నిర్ధారించుము.

ఆహార పదార్థం	(పిండి పదార్థం ) ఉంది/లేదు
1. అన్నము	పిండి పదార్థం ఉంది.
2. గుడ్డు సొన	పిండి పదార్థం లేదు
3. గోధుమపిండి	పిండి పదార్థం ఉంది

కృత్యం -2

ప్రశ్న 3.
వేరుశనగ గింజలలో క్రొవ్వుల ఉనికిని ఎలా నిర్ధారిస్తావు?
జవాబు:
ఉద్దేశం : వేరుశనగ గింజలలో కొవ్వుల ఉనికిని నిర్ధారించుట.

ఏం కావాలి :

1. వేరుశనగ గింజలు
2. తెల్లకాగితం
3. పింగాణీ కల్వం,

ఎలా చేయాలి :
ఒక పింగాణీ కల్వంలో పది వేరుశనగ గింజలను తీసుకొని మెత్తని పేస్ట్ తయారుచేసుకోవాలి. పేస్టు తెల్ల కాగితంపై ఉంచి కొన్ని సెకన్ల పాటు రుద్దండి. కాగితంపై కొంత సమయం ఉంచండి. తెల్లకాగితం పారదర్శకంగా లేదా అర్ద పారదర్శకంగా మారితే వేరుశనగ గింజలలో క్రొవ్వు లేదా నూనె ఉంటుందని నీవు చెప్పవచ్చు.

ఏం చూశావు :
తెల్లకాగితం పారదర్శకంగా మారింది.

ఏం నేర్చుకున్నావు :
వేరుశనగ గింజలలో క్రొవ్వులు ఉన్నాయి.

ఆహారపదార్థం	క్రొవ్వులు ఉన్నవి / లేవు
1. వడ/బజ్జీ	క్రొవ్వులు ఉన్నవి
2. బియ్యంపిండి	క్రొవ్వులు లేవు
3. పాలకోవా	క్రొవ్వులు ఉన్నాయి

కృత్యం -3

ప్రశ్న 4.
వివిద ఖనిజ లవణాల వనరులను వాటి ప్రాముఖ్యతను తెలపండి.
జవాబు:

ఖనిజ లవణాలు	వనరులు	ప్రాముఖ్యత
కాల్షియం (Ca)	పాలు, పెరుగు, ఆకు కూరలు, చేప మొ||	దృఢమైన ఎముకలు మరియు దంతాలకు.
ఇనుము (Fe)	మాంసము, ఎండిన ఫలాలు, ఆకుపచ్చని ఆకుకూరలు మొదలైనవి.	రక్తం ఏర్పడడానికి, ఆక్సిజన్ రవాణాకు.
భాస్వరం (P)	పాలు, పెరుగు, ధాన్యాలు, గింజలు, మాంసం మొదలైనవి.	బలమైన ఎముకలు, దంతాలు తయారుకావడానికి.
అయోడిన్ (I)	సముద్ర ఆహారం, అయోడిన్ ఉప్పు మొ||	థైరాయిడ్ హార్మోన్ తయారీకి. లోపించినచో, గాయిటర్ వ్యాధి కలుగుతుంది.
సోడియం (Na)	ఉప్పు	శరీరానికి కావలసిన నీటిని పట్టి ఉంచుతుంది.

అయోడిన్ పొందటానికి నీవు ఏ ఆహారం తీసుకొంటావు?
జవాబు:
సముద్ర ఆహారం, అయోడిన్ ఉప్పు

ఇనుము అధికంగా కలిగిన ఆహారపదార్థాలు ఏమిటి?
జవాబు:
ఎండిన ఫలాలు, ఆకుపచ్చని కూరలు

కృత్యం -4.

ప్రశ్న 5.
విటమిన్ సి నిర్ధారణ కొరకు సులువైన పరీక్ష చేద్దాం.
జవాబు:
ఉద్దేశం : నిమ్మపండ్లలో విటమిన్-సి ఉనికిని నిర్ధారించడం.

ఏం కావాలి :

1. నిమ్మరసం
2. అయోడిన్ ద్రావణం
3. తెల్లకాగితం ముక్క
4. చాకు
5. డ్రాపర్.

ఎలా చేయాలి :
నిమ్మకాయను రెండు ముక్కలు చేయండి. తెల్లకాగితం ముక్కపై అయోడిన్ ద్రావణంను రెండు లేదా మూడు చుక్కలను వేయండి. నిమ్మకాయ ముక్కను కాగితంపై బోర్లించి ఉంచండి. కొన్ని నిమిషాలు అలా ఉంచి, గమనించండి. విటమిన్-సి ఉన్నట్లయితే, నిమ్మబద్ద క్రింద కాగితం రంగును కోల్పోతుంది.

ఏం చూశావు :
నిమ్మబద్ద క్రింద ఉన్న పేపరు రంగు మారింది. ఏం నేర్చుకున్నావు : నిమ్మకాయలో విటమిన్-సి ఉన్నది.

కృత్యం – 5

ప్రశ్న 6.
వేర్వేరు ఆహార పదార్థాలను గుర్తుకు తెచ్చుకోండి మరియు అది కలిగి ఉన్న పీచు పదార్థ పరిమాణాన్ని బట్టి వాటిని వర్గీకరించండి. మీ జట్టులో చర్చించి, కింది పట్టిక నింపండి. మీ కోసం ఒక ఉదాహరణ ఇవ్వబడింది.

జవాబు:

ఎక్కువ పీచు పదార్థాలు	తక్కువ పీచు పదార్థాలు	పీచు పదార్థాలు లేనివి
1. నారింజ	ద్రాక్ష	పాలు
2. కమలాలు	మామిడి	నెయ్యి
3. చిలకడ దుంప	సపోటా	చేప
4. బీరకాయ	జామ	మాంసం
5. చిక్కుడుకాయ
6. తోటకూర

కృత్యం – 6

ప్రశ్న 7.
ఆహారంలో నీటి ప్రాధాన్యతను తెలపటానికి నీవు నిర్వహించే ప్రయోగం ఏమిటి?
జవాబు:
ఉద్దేశం : నీటి వాడకాన్ని తెలుసుకోవడం.

ఏం కావాలి :

1. స్పాంజ్ ముక్క
2. ప్లాస్టిక్ పైప్
3. నీరు
4. బకెట్.

ఎలా చేయాలి :
స్పాంజి ముక్క తీసుకొని పైపు ద్వారా పంపడానికి ప్రయత్నించండి. అది కొంచెం కష్టంగా కదులుతుంది. పైపు నుండి స్పాంజిని తొలగించండి. దానిని నీటిలో ముంచి, మరలా పైపు గుండా మళ్ళీ ప్రయత్నించండి.

ఏం చూశావు :
స్పాంజ్ ముక్క పైపు ద్వారా సులభంగా కదిలినది.

ఏం నేర్చుకున్నావు :
పేగు వంటి ఇరుకైన గొట్టాలలో పదార్థం సులువుగా కదలటానికి నీరు సహాయపడుతుంది.

కృత్యం -7

ప్రశ్న 8.
ఈ కింద మనం సాధారణంగా తీసుకొనే ఆహారపదార్థాల జాబితా ఉంది. వాటిని ఈ కింది పట్టికలోని గడులలోని అంశాల ఆధారంగా వర్గీకరించి, పట్టికలో నింపండి. ధాన్యాలు, దుంపలు, నూనెలు, స్వీట్లు, కొవ్వులు, పప్పుధాన్యాలు, గింజధాన్యాలు, విత్తనాలు, పాల ఉత్పత్తులు, చేపలు, గుడ్లు, మాంసం, ఆకుకూరలు, పండ్లు, కూరగాయలు.

జవాబు:

శక్తిని ఇచ్చే ఆహార పదార్థాలు (పిండిపదార్థాలు, క్రొవ్వులు)	శరీర నిర్మాణ ఆహారపదార్థాలు (మాంసకృత్తులు)	రక్షణ ఇచ్చే ఆహారపదార్థాలు (విటమిన్లు, ఖనిజ లవణాలు)
1. ధాన్యాలు	పప్పుధాన్యాలు	ఆకుకూరలు
2. దుంపలు	గింజధాన్యాలు	పండ్లు
3. నూనెలు	విత్తనాలు	కూరగాయలు
4. స్వీట్లు	పాల ఉత్పత్తులు
5. క్రొవ్వులు	చేపలు
	గుడ్లు
	మాంసం

మీరు తీసుకొనే ఆహారంలో ఇవన్నీ ఉన్నాయా?
జవాబు:
అవును.

వాటిని మీరు ఎంతెంత పరిమాణంలో తీసుకుంటున్నారు?
జవాబు:
పిండిపదార్థాలు అధిక పరిమాణంలోనూ, మాంసకృత్తులను తగు పరిమాణంలోనూ, విటమిన్స్ క్రొవ్వులను తక్కువ పరిమాణంలో తీసుకొంటున్నాము.

AP State Syllabus AP Board 7th Class Science Important Questions Chapter 16 Forest: Our Life

AP State Syllabus 7th Class Science Important Questions 16th Lesson Forest: Our Life

7th Class Science 16th Lesson Forest: Our Life Important Questions and Answers

Question 1.
What happened to the habitat of a forest due to deforestation?
Answer:

1. The natural habitat of a forest is lost when forests are cut down.
2. Several types of organisms disappear (either die out or leave the place)

Question 2.
Why are forests very important for us?
Answer:

1. Forests are renewable natural resources, which play an important role in the maintenance of ecological balance.
2. They are an important source of timber, fuelwood, cane, resins, lac, oils, fruits, nuts, fire honey etc.
3. The forests also have wild strains of cultivable crops and medicinal plants.
4. If affected by a disease, the whole forest area is not destroyed.
5. They provide habitat to wildlife.
6. Forests help to control soil erosion.
7. They help in causing rain.
8. They keep the surrounding cool.

Question 3.
Why should not we cut the forests?
Answer:

1. Forest is a place where there are many different trees.
2. It is a home for wild animals.
3. It also decorates the world.
4. It is a very airy and shadowy place.
5. We should not cut them to build factories, buildings etc or to grow crops, orchards etc.

Question 4.
Give a list of the trees, animals living in the forest areas of different districts in A.P and T.S.
Answer:

Question 5.
How is the destruction of forests taking place? What are the reasons for this destruction?
Answer:

1. Usually, people destroy the forest for their own economic purposes for example, earning by selling trees and thus, excessive cutting down of trees or deforestation takes place.
2. Deforestation also takes place when forests are cleared to construct buildings, roads,
   industries etc. ‘
3. Nowadays thermal, nuclear power plants, mining industries led by multinational companies are a major threat to forests throughout the globe.
4. Often large parts of forests are also lost due to forest fires.

Question 6.
When led to the Chipko movement in history?
Answer:

1. In 1730 AD about 350 Bishnois led by Amrita Devi sacrificed their lives to protect sacred green Kejari trees by hugging them when a king wanted to cut those trees later this was led to the Chipko movement in history.
2. Thereafter this practice has been carry forward by people like Sunder Lai Bahuguna.

Question 7.
Narrate the story written by R. Ramya a student of VIII ofZPH School, Nellore.
Answer:

1. There is a school in a village. The school has no boundary wall. The Headmaster arranged for the construction of a boundary wall with the help of higher authorities.
2. They were measuring the boundaries.
3. There was a mango tree in the school. The tree was on the boundary line. A person staying next to the school argued that the tree belonged to him.
   
4. The children studying in the school had been playing, reading, having lunch etc for years under the tree.
5. The children came to know that the person sold the tree. It was going to be cut very soon. They tried to convince that person not to remove the tree, but he adamantly denied the children’s request.
6. Neelima who was studying class VII was worried about it.
7. She thought throughout the night and got an idea. The next morning she told the idea to her friends. They
   collected money from their savings.
8. All the children went into the village and collected some more money. They went to that person and gave him all the money they collected.
9. Seeing the concern of the children, the person agreed that the tree would not be cut.

Question 8.
Write about the forest fire.
Answer:
Forest fire:

1. Forest fire occurs naturally and sometimes with human interference. It requires more time to control forest fire.
2. Heavy loses are incurred because of the rapid spread of fire.
3. The people who live in forest region should be alert in order to escape the danger of forest fire.

Question 9.
Write the names of some famous forests in our country. How are they now?
Answer:

1. In ancient times the country was famous for its dense and continuous forests like Dandakaranya, Panchavati, Nallamala etc.
2. But with the advance of civilization through ages, most parts of these forests are gone now.

Question 10.
Why are forests has been cut down?
Answer:
Forests have been cut down at a very fast rate in the past hundred years and replaced by industries, orchards (plantations of fruit-bearing plants) or those needed for timber or other economic needs, croplands etc.

AP State Syllabus AP Board 7th Class Science Important Questions Chapter 15 Soil: Our Life

AP State Syllabus 7th Class Science Important Questions 15th Lesson Soil: Our Life

7th Class Science 15th Lesson Soil: Our Life Important Questions and Answers

Question 1.
Describe the distinct horizontal layers of the soil. What are these layers made up of (or) Describe the soil profile.
Answer:
Soil is made up of distinct horizontal layers. These layers are called horizons. They range from rich, organic upper layers (humus and topsoil) to underlying rocky layers (subsoil, regolith and bedrock).

1. O Horizon – The top, organic layer of soil, made up mostly of leaf litter and humus (decomposed organic matter).
2. A horizon – The layer called top soil. It is found below the O horizon and above the E horizon. Seeds germinate and plant roots grow in this dark-colored layer. It is made up of humus (decomposed organic matter) mixed with mineral particles.
3. E Horizon – This eluviation (leaching) layer is light in colour. This layer is beneath the A horizon and above the B Horizon. It is made up mostly of sand and silt, having
   lost most of its minerals and clay as water drips through the soil (in the process of eluviation).
4. B Horizon – Also called the subsoil – this layer is beneath the E Horizon and above the C Horizon. It contains clay and mineral deposits (like iron, aluminum oxides and calcium carbonate) that it receives from layers above it when mineralized water drips from the soil above.
5. C Horizon – Also called regolith. The layer beneath the B Horizon and above the R Horizon. It consists of slightly broken-up bedrock. Plant roots do not penetrate into this layer. Very little organic material is found in this layer.
6. R Horizon – The unweathered rock (bedrock) layer that is beneath all the other layers.
   These different layers of soil are called soil profiles.

Question 2.
What type of soil is available in Veerapanayanipalli village of Kadapa District? Which crops grow there? Which substances are found in that soil?
Answer:

1. In Veerapanayanipalli village of Kadapa District, we have black soil. We can make a ball by using this soil.
2. But we can make cracked rings only. So it is light clay soil.
3. Farmers grow Cotton and Mirchi.
4. If you dig two or three feet we will get limestone in the soil.
5. We use those stones for different purposes like the construction of compound walls etc.

Question 3.
Describe the soil structure in the Krishnapuram of Chittoor district. What crops do farmers grow there?
Answer:

1. Krishnapuram is a village in Chittoor District.
2. This village had red soil. We can make a ball with this soil. We cannot make a ring with it as it contains sand also.
3. In this soil farmers grow groundnut and castor. In some places cotton is also grown.
4. People call it as red sand soil.

Question 4.
Give a brief note of the soil and the crops grown in the village Dantaguntla of Krishna District. Is there any village in any district with the same type of soil?
Answer:

1. Dantaguntla is a village in Krishna district.
2. Black soil is there in that village. As this is sticky in nature we can make any type of model using this soil.
3. This soil retains water for a long time.
4. Farmers grow cotton, sugar cane and paddy in this soil.
5. In Indukurupeta village of Nellore district, the same type of soil is available.

Question 5.
What type of soil is available in Kanala village of Kurnool district. What is the nature of the soil there and the crops the farmers grow there?
Answer:

1. Kanala is a village in Kurnool District.
2. With this soil we can make only cracked rings. This soil contains sand also.
3. Farmers grow Jowar, Bengal Gram, and Paddy in this soil.

Question 6.
Describe the soil nature available in Ramapuram of Prakasam District. Which crops are grown there?
Answer:

1. Ramapuram is a village in Prakasam District.
2. Here the soil is sandy soil. This soil is not suitable even to make a ring.
3. Farmers grow Jasmine, Kanakambaram like flowers only. Most of the farmers practice Aquaculture.
4. Paddy is not grown in this village.

Question 7.
Which type of soil is generally seen in our state?
Answer:
In our state we see the following types of soils.
а) Black soil b) Red soil c) Sandy soil.

Question 8.
What is soil erosion?
Answer:

1. During heavy winds we observe that the surface soil particles are carried away by air.
2. Sometimes during heavy rains, rainwater carries away top layers of soil.
3. This is called soil erosion.
4. As a result of storms and floods, fertile soil layers are removed and the soil becomes barren.

Question 9.
How can soil erosion be prevented?
Answer:

1. Our farmers grow big trees around the fields to stop winds.
2. They don’t keep the lands vacant.
3. Farmers generally use vacant lands to grow grass and other plants.
4. These grass plant roots hold the soil particles and prevent soil erosion during heavy rains.

Question 10.
What do farmers do to preserve the fertility of the soil?
Answer:

1. It is very important to preserve the fertility of the soil.
2. You know farmers can’t continue the same type of crops in their fields.
3. They know continuous cultivation of the same agriculture crops reduces soil fertility.
4. Generally, farmers cultivate pulses after the completion of paddy.
5. This kind of rotation of crops retains soil fertility and productivity.
6. Conservation of soil is an important factor in agriculture.

Question 11.
How is the formation soil happened why are farmers and Engineers testing the soil?
Answer:
Soil Formation:

1. Soil is formed slowly as rock (the parent material) erodes into tiny pieces near the Earth’s surface.
2. Organic matter decays and mixes with inorganic material (rock particles, minerals and water) to form soil.
3. These days farmers test the soil in the field using soil technologies in order to grow suitable crops in the fields.
4. Engineers also test the soil profile before constructing multistoried buildings, bridges and dams.

Question 12.
What is soil science?
Answer:

1. Soil science is the study of soil as a natural resource on the surface of the Earth.
2. This includes soil formation, classification and mapping, physical-chemical – biological and fertility properties of soil.
3. Sometimes terms that refer to branches of soil science such as pedology and edaphology are used as if synonymous with soil science.
4. The study of formation, chemistry, morphology and classification of soil is called pedology.
5. The study of the influence of soil on organisms, especially on plants is called edaphology.
6. The diversity of names associated with this discipline is related to the various associations concerned.
7. Indeed engineers, agronomists, chemists, geologists, physical geographers, ecologists, biologists, microbiologists, silviculturists, archeologists all contribute to further knowledge of soil and the advancement of soil science.

Question 13.
How do you determine the moisture content in the soil given to you? Describe the experiment you perform.
Answer:
The moisture content in the soil.

1. There are many ways of finding out the moisture content of different soils. We shall use a simple method.
2. Grind the soil you wish to find the moisture content of, into a fine powder.
3. Weigh 100 gm of soil from this pile. Spread it on a newspaper and dry it for about two hours in the sun.
4. While drying the soil, the sky must be clear and the heat of the sun intense.
5. Keep turning the soil over while you are drying it. Be careful that the soil does not spill out of the newspaper.
6. Weigh the soil again after it has completely dried.
7. The difference in the two weights will tell you how much water 100 gm of the soil contained.
8. This quantity is known as the percent moisture content of the soil.

Question 14.
How do you determine the percolation rate of the given soil? Describe the activity you do.
Answer:

1. Take soil samples.
2. Take a plastic funnel and place a filter paper in it as shown in figure.
   
3. Weigh 50 gm of dry soil and pour it into the funnel.
4. Take 100 ml of water in a measuring cylinder.
5. Then pour the water on the soil drop by drop.
6. Do not let all the waterfall at one spot.
7. Pour water all over the surface of the soil until it starts dripping out of the funnel.
8. Observe how fast water passes down the soil.
9. Measure the amount of water collected in the beaker.
10. Calculate the difference between amounts of water.
11. By taking different soils in the funnel and calculating the difference between amount of water we can determine the percolation rate of different soils.

Question 15.
Describe the experiment to find out the substances present in the soil.
Answer:

1. Fill a beaker half full with soil. Pour some rainwater or distilled water over the soil.
2. We should pour enough water to fill the beaker three-fourths.
3. Stir the soil and water with a twig. Then let the solution stand for some time.
4. Once the soil settles down, drain out the water carefully.
   
5. Fill a boiling tube half full with this drained water.
6. Heat the boiling tube over a candle flame. Continue heating till only a fourth of the water remains.
7. Note the color of the water. Use litmus paper to test whether the water is acidic or basic.
8. Soils contain minerals. Most of the minerals found in the soils are salts of sodium, calcium, magnesium and potassium chlorides, sulfates and carbonates.
9. Highly acidic soil retards plant growth by affecting the efficiency with which the plant absorbs nutrients from the soil.

Question 16.
Draw the line diagram to identify the different types of soils.
Answer:

1. We can identify the different types of soils in the line diagram given below.
2. We can determine the soil on the basis of the following chart.
   

Question 17.
Draw the diagram showing different Horizons of the soil.
Answer:

Question 18.
‘Soil is a good habitat’ Explain the statement.
Answer:

1. Soil is a good habitat. We depend on it for agricultural and construction purposes, making utensils, toys etc.
2. We know that plants depend on soil for nutrients like mineral salts and water from the soil
3. Animal life such as burrows or eggs of insects are found in the soil.

Question 19.
What is pottery? What type of industry is it?
Answer:
Pottery: Making pots by using soil is called a pottery.

1. This is an ancient creative occupation.
2. During Harappan civilization, different varieties of designer pots and clay utensils were used.
3. Pottery is a cottage industry in our country.
4. Potters make pots by using clay soil on a pottery wheel.
   

Question 20.
Complete the below list.
Answer:

Question 21.
Why should we use clay idols instead of idols made of plaster of Paris?
Answer:

1. During festivals like Vinayaka Chavithi, we use idols of Ganesh made of plaster of Paris and chemical colors which causes severe damage to our environment.
2. Instead of these chemical idols we should use clay idols and celebrate festivals in an eco-friendly way.

Question 22.
Read the below table and answer the following questions.

Type of Soil	Character of Soil
Clay Soil	easy to roll into a ball
Loam soil	breaks on bending
Light clay	easy to make a ring
Sandy soil	not easy to roll into a ball

a) What is the character of loam soil?
b) What is the difference between clay soil and sandy soil?
Answer:
a) When you try to make a cylinder, it can break. This is the light loam soil.
b)

AP State Syllabus AP Board 7th Class Science Important Questions Chapter 14 Water – Too Little To Waste

AP State Syllabus 7th Class Science Important Questions 14th Lesson Water – Too Little To Waste

7th Class Science 14th Lesson Water – Too Little To Waste Important Questions and Answers

Question 1.
How is water distributed on the globe? How much of freshwater is available to us?
Answer:

1. If the total water on earth be 100%, the percent fresh water available to us is only 1%.
2. 

Question 2.
When was the international decade for action on ‘water for life’ declared?
Answer:

1. On World Water Day, that is 22 March 2005, the period 2005 – 2015 was declared as the International Decade for action on “Water for Life”.

Question 3.
What would you do for the cause ‘water for life”?
Answer:

1. Normally a lot of water flows out of the kitchen as well as bathrooms in our houses.
2. Many of us do not know that water is being wasted in this way.
3. We must make a channel of water to flow from kitchen to the garden around.
4. We cannot wastewater from the bathroom also. It could be used after purification.

Question 4.
Why do we need proper drainage system?
Answer:

1. We dispose of wastewater in our daily life in different ways and means.
2. We often see water stagnated near bore wells or beside houses.
3. Sometimes human and animal excretions also mix with this water.
4. We get a foul smell when we walk near those areas.
5. To prevent this we need a proper drainage system.

Question 5.
How do you find out what realty happens to waste water at treatment plants?
Answer:

1. Fill a large glass jar 3/4 full of water. Add some dirty organic matter such as grass pieces or orange peels, a small amount of detergent, and a few drops of an ink or any colour.
2. Cap the jar, shake it well and let the mixture stand in the sun for two days.
3. After two days, shake the mixture and pour a small sample into test tube. Label this test tube “Before treatment; Sample 1”. How does it smell?
4. Use an aerator from an aquarium to bubble air through the sample in the glass jar. Allow several hours for aeration; leave the aerator attached overnight. If you do not have an aerator, use a mechanical stirrer or a mixer. You may have to stir it several times. This actually works like a skimmer of the wastewater treatment plant.
5. Aeration causes organisms that break down waste to grow faster thus it leads to what is called as “Biological Process”.
   
6. The next day when aeration is complete, pour another sample into a second test tube. Label it “After aeration; Sample 2”.
7. Fold a piece of filter paper to form a cone. Wet the paper with tap water and then insert the cone in a funnel. Mount the funnel on a support.
8. Place layers of sand, fine gravel and finally medium gravel in the funnel.
9. Pour the remaining aerated liquid through the filter into the beakers. Do not allow the liquid to spill over the filter. If the filtered liquid is not clear, filter it a few times till you get clear water. This is “physical process”.
10. Pour a sample of the filtered water into a third test tube labeled “Filtered’ Sample 3”.
11. Pour another sample of the filtered water into a fourth test tube. Add a small piece of a chlorine tablet. Mix well until the water is clear. Labe! the test tube “Chlorinated; Sample 4”.
12. This is a “Chemical Process” of treatment.
13. Observe carefully the samples in all the test tubes. Do not taste! Just smell them!
14. We can easily under stand how the wastewater is recycled in the treatment plant.

Question 6.
For which purposes are we using freshwater?
Answer: Freshwater has been the constant and essential companion of human beings throughout history. Water is used in great quantities in agriculture and industries.

Question 7.
How is freshwater distributed over the globe?
Answer:

1. Our globe is poorly endowed with fresh water.
2. Most water is rendered useless to humans by dilution with salt in the oceans.
3. Only 2.5 percent is available as freshwater of which 2/3 is locked up in Ice and snow.
4. Nature is unkind in depositing almost eighty percent of rain over the sea.
5. The rain that falls over the land has a great potential value.

Question 8.
What is causing water scarcity? Write the principle ways which are degrading the quality and quantity of natural supply of fresh water.
Answer:

1. Unsustainable extraction of fresh water causes water scarcity.
2. Due to the over-extraction of fresh water underground reserves are falling rapidly.
3. In India, the water table has fallen more than 300 meters’.
4. Human interventions which degrade the quality and quantity of the natural supply of fresh water occur, in 3 principal ways.
5. Firstly dams alter the natural flow of rivers often leading to water scarcity.
6. Secondly, soil moisture is lost by land degradation due to poor farming practices
   and deforestation.
7. Thirdly, surface water is polluted by run-off chemicals used in industries and households.

Question 9.
How can you say that the next cold war could be over water?
Answer:

1. The world population is projected to grown 9.3 Billion by 2050.
2. In addition to safe drinking water and sanitation, the rising pressure on freshwater will be felt most severely in the energy and food sectors.
3. Two out of three people will be living with water shortage by 2025.
4. The growth of demand the decline in freshwater availability, the adverse health effects from poor water quality and scarcity will result in violence and water wars.
5. The next cold war could be over water.

Question 10.
How can we conserve water? Write some practices that can be adopted.
Answer:
a)

1. We perform many activities in our daily life using water.
2. We can conserve water by adopting certain good practices,

b) Some practices that can be adopted:

1. Water is precious. We should not waste it.
2. Collect water in a bucket after cleaning rice, dal and vegetables in the kitchen which contains peels of vegetables.
3. We can use this water for our cattle.
4. We should not throw solid food remains, tea leaves and oily wastes down the drain.
5. We must make a channel so that the kitchen and bathroom water flows to the coconut and banana plants in our garden.
6. We should use only mild soaps and detergents so that this water may not harm our plants.
7. Any leakage of water from any tap must be repaired immediately.

AP State Syllabus AP Board 7th Class Science Important Questions Chapter 9 Reflection of Light

AP State Syllabus 7th Class Science Important Questions 9th Lesson Reflection of Light

7th Class Science 9th Lesson Reflection of Light Important Questions and Answers

Question 1.
When will you be able to see clear image of yourself in a plane mirror?
Answer:

1. Point a torch towards the mirror so that it’s light falls on the mirror which we hold up as shown in figure (a), and try to see our image in the mirror.
   
2. Now turn the torch towards our face as shown in figure (b), and see our image in the mirror.
   
3. We will find that when light is focused on our face we can see our image clearly in the mirror.
4. We also notice that when light is focused on the mirror we find a dim image of our face in the mirror.

Question 2.
Explain by a simple activity what are incident and reflected rays of light. What is reflection of light?
Answer:

1. Place a blank sheet of paper on the ground such that part of it is in the sunlight and other part of it is in the shadow.
2. Hold the mirror strip with the slit facing the sun.
3. Let a ray of light from the slit fall on the paper.
4. Now take another mirror strip and place it in the path of this light ray such that the ray coming from first mirror falls on the second mirror as shown in figure.
   
5. We did not see any other ray of light, apart from the one from the mirror slit, on the paper.
6. This effect of the mirror strip on the ray of light is called reflection.
7. The ray of light falling on the mirror is called the incident ray and the ray returning from it is called the reflected ray.

Question 3.
Explain the terms ‘Angle of incidence’, ‘Angle of reflection’ and ‘Normal at the point of incidence.’
Answer:

1. Take a sheet of blank paper. Draw a line segment AC across the middle.
2. Draw another straight fine at right angles (90 degrees) to segment AC.
3. The second line should bisect segment AC at point B. We shall call this line as Normal. See in figure, (a)
   
4. Draw two lines from point B on the left side of the normal and two on the right side. The lines should be at angles of 30° and 60° respectively from the normal. Number these lines 1, 2, 3, 4 as shown in figure, (b)
   
5. Place a mirror strip vertically on segment AC with its reflecting surface facing the normal.
6. See that the back of the mirror coincides with segment with a slit and let its light ray fall along line 4.
7. Now this ray is the incident ray for the mirror.
8. The angle between the normal and the incident ray is called the Angle of Incidence (∠i).
9. The angle between normal and the reflected ray (along line 1) is called the Angle of Reflection (∠r).
10. Adjust the mirror strip with the slit so that its light ray falls along line 3 and we find that the reflected ray falls along line 2.
11. Adjust the mirror strip with the slit so that its light ray falls along normal, then the angle of incidence is 0° (the angle between normal and incident ray “that is also normal here”, is 0°)
12. The reflected light reflects back along the normal itself.

Question 4.
What relationship exists between angle of incidence and angle of reflection? State it and prove the relation by a simple activity.
Answer:

1. In the case of reflection on mirrors the law of reflection is Angle of incidence ∠i = Angle of reflection ∠r.
2. Proof : by a simple activity.
   • Take a sheet of blank paper. Draw a line AC on it.
   • Draw another straight line at right angles to AC.
   • This line should bisect AC. This line is normal.
   • Draw two lines from point B on the left side of the normal and two lines on the right side of the normal.
   • The lines should make angles of 30° and 60° respectively from the normal. Number these lines as 1, 2, 3 and 4 as shown in figure.
     
   • Place the mirror strip vertically on AC. With its reflecting surface facing the normal.
   • Take the mirror strip with a slit and let its light ray fall along line 4.
   • We find the reflected ray coming along the line 1.
   • Note the angle of incidence and angle of reflection.
   • Repeat the experiment by sending the light ray along line 3.
   • The reflected ray is found to be along line 2.
   • Record the observations.
     
     It is clear from the above activity that angle of incidence ∠i = angle of reflection ∠r.

Question 5.
Describe a small activity to prove that it is possible to see the image of an object only when the incident ray, reflected ray and normal are at the same plane.
Answer:

1. Place a mirror (1ft. × 1ft.) on the floor. You and your friends A, B, C stand on four sides of the mirror as shown in figure.
2. Adjust your places of standing, in such a way that each one of you can see the image of the person opposite to you in the mirror kept on the floor.
3. Your friends A, C are able to see images of each other in the mirror.
4. Ask your friend – B, who is in front of you to move a feet aside from his place. You cannot see his image in the mirror.
   
5. Imagine a normal to the mirror. It would be perpendicular to the mirror as well as to the floor.
6. Imagine an incident ray coming from your friend B, falls on the mirror then the reflected ray from mirror reaches you.
7. Observe that the incident ray, reflected ray and normal lie in the same plane.
8. Now think why the image of your friend B is not visible to you when he moves aside. Where should.you stand to see his image? Once again imagine the incident, reflected rays and normal and assumed plane.
9. It is evident that the incident ray, reflected ray and normal should be in same plane, then only you can see your friend.

Question 6.
How would you get an image in a mirror?
Answer:

1. We see our image in a mirror many times. How it is formed?
2. During day time the light which falls on us gets reflected and a number of reflected light rays from us that fall on the mirror also get reflected back.
3. These reflected rays reach your eye and make us see our image.
4. See figure (a). Thus formation of image in mirrors is due to reflection of light rays from the mirror.
   
5. See the figure (b) and observe the lines. They will explain how the image of a candle is formed in the mirror and how we are able to see the image of the candle in the mirror.
   

Question 7.
What is the difference between you and your image in a mirror?
Answer:

1. Stand in front of a mirror as shown in figure (a) and observe on which side of you does the pocket on your shirt appear, when you look into the mirror.
   
2. Raise your right hand infront of a mirror as shown in figure (b). Which hand of your image appears raised?
3. To make your image to comb hair with its right hand, what will you have to do?
4. What do these observations suggest?
5. In a mirror, right of an object appears as left and left of the object appears as right.
6. Note that only sides are interchanged. This is called lateral inversion.

Question 8.
How can you make a garden in a box ? Describe the procedure.
Answer:

1. Take an empty shoe box. Place two plane mirrors along the edges.
2. See that the pair of mirrors are parallel to each other and their reflecting surfaces face each other as shown in figure.
   
3. Scratch the centre part of a mirror at its back and make a hole to the wall of the box such that it coincides with the scratched portion of the mirror.
4. Put some flowers in the box. Make a few holes in the lid before closing the box so that light enters into the box.
5. Now look through the hole. You can see a wonderful and beautiful vast garden.

Question 9.
Why does the small area look like a vast garden?
Answer:

1. The light which enters the box falls on the flowers, gets reflected and travels in all directions.
2. The rays which fall on the mirrors reflect back to the opposite mirror.
3. This process happens again and again.
4. Due to this multiple reflection we can see that small area as a big garden.

Question 10.
Explain what do you understand by regular reflection and irregular reflection.
Answer:

1. Reflection from a smooth surface like that of a mirror is called regular reflection (see figure a).
2. Clear images are formed in case of regular reflection.
3. Reflection from a rough or irregular surface is called irregular reflection or diffused reflection (see figure b).
4. Images are not clear in case of irregular reflection.
5. In some cases we can’t find the image at all.
   

Question 11.
Can we use rear view mirror in place of plain mirror? Yes /No give the reason.
Answer:
No. We cannot use rear view mirror in place of plane mirror. The reasons are:

1. In plane mirror we can see our images.
2. But in rear view mirror we cannot see our images. So there is no use to use rear view mirror.

Question 12.
A mirror is hanging in your room. Your friend is sitting in the same room in a chair. If your friend wants to see you in a mirror, how will you adjust your position? Explain. ’
Answer:
I will adjust my position according to the laws of reflection. According to the laws of reflection Angle of incidence = Angle of reflection. If my friend wants to see me in a mirror, I will adjust my position (i.e) the angle of incidence is equal to angle of reflection. Then my friend will see me in that mirror.

Question 13.
What are rays of light? How do you produce rays of light?
Answer:

1. Take a mirror strip and a black paper as shown in figure, (a)
2. Cover the mirror strip with black paper and cut a 1 mm wide slit in the black paper, as shown in figure b.
3. Hold the mirror strip with the slit facing the sun as shown in figure, (c).
   
4. We will see some light coming through the slit. Let this light fall on a sheet of paper spread on the ground.
5. Light coming from such a slit or any other small hole looks like a ray of light.

Question 14.
Why should we keep mirror strips parallel to each other in periscope? What happens if they are not parallel?
Answer:

1. In a periscope the incident ray for the second mirror is the reflected ray of the first mirror.
2. When these two mirrors are parallel to each other, only then the rays lie in the same plane and can pass through the windows of the periscope.
3. If these mirrors make some angle with each other, then the reflected ray of the first mirror may not reach the second mirror or the reflected ray of second mirror may not pass through the window of periscope.
4. In both cases we can’t see the object with the periscope.

Question 15.
Can you spell your name as it appears in a mirror? Spelling of my name is …………………..  It appears in the mirror as ……………
Answer:
The student has to do it.

Question 16.
Show that the size of an object and its image are same.
Answer:

1. Stand in front of a big mirror. Observe your image.
2. Step back two feet and step forward one foot. Observe your image while you move to and fro.
3. You notice that your image also move.
4. Estimate the distance from you to the mirror and the distance from the mirror to the image.
5. Is the size of your image equal to your size? Place an object in front of the mirror. Compare the size of the object with its image.
6. We notice that irrespective of the size of mirrors, the size of image and the size of object are equal.

Question 17.
How are multiple images of an object formed?
Answer:

1. Take two plain mirrors of same size and join them with a cellophane tape as shown in figure.
   
2. Fold the mirrors through certain angle and place an object between them. We see multiple images of the object.
3. Count the number of images after changing the angle between the mirrors.
4. If we change the angle between the mirrors the number of images of the object also changes.

Question 18.
Explain the formation of images with spherical mirrors.
Answer:

1. Place the concave and convex mirrors on two different V – stands.
2. Put two candles of same size in front of them as shown in figure.
   
3. Adjust the position of candles, to form clear images in the mirrors.
4. Observe the sizes of images.

Question 19.
What are real and virtual images? Explain with the help of an activity.
Answer:

1. Place a concave mirror on a V-stand.
2. Place a lighted candle in front of it. Place a thick white paper or white drawing sheet behind the candle.
3. This acts as a screen. See figure.
   
4. Adjust distances between candle and mirror, screen and mirror by moving them either forward or backward till a clear image appear on the screen.
5. Repeat the activity using a convex mirror and plane mirror in place of concave mirror.
6. The image that can be obtained on a screen is called a Real Image. We can see this image in the mirror too.
7. The image that can’t be obtained on a screen but can be seen only in the mirror is
   called a virtual image.

Question 20.
Explain how are we able to see the objects around us in day time?
Answer:

1. We already know that, to see any object, light should fall on it.
2. In daytime we are able to see all objects which are in our room even though sunlight does not fall directly on those objects.
3. The multiple reflection of sunlight from surfaces like wall, floor, ceiling etc, finally falls on the object and gets reflected by it and reaches us.
4. This enables us to see the object.

Question 21.
How do you make a periscope?
Answer:

1. We have to secure the following materials to make a periscope. Empty agarbatti box, two mirror strips, scale, pencil, blade, match box, candle, glue.
2. Close both ends of the agarbatti box. Draw squares at both ends.
3. Draw the diagonal to these squares as shown in figure.
4. Slit the diagonals with a blade. The slits should equal to the length of the mirror strips.
5. Fix the mirror strips in these slits as shown in figure (b). Take care to see that these mirror strips lie parallel to each other, with their reflecting surfaces facing each other.
   
6. Fix the mirror strips firmly to the box with a few drops of molten wax from a burning candle. We can also use glue or fevicol instead of wax.
7. Cut out two windows on the narrow sides of the box as shown in figure (c). The windows should open directly on the reflecting surfaces of the mirror strips.
8. Now the periscope is ready.

Question 22.
How would you use the periscope?
Answer:

1. When we look through window 2, We will be able to see things lying in front of window 1.
2. We hide behind a tree, we can easily see that is happening on the other side of the tree with this periscope.
   
3. Observe in figure the girl is viewing objects outside the room through the window while hiding herself in the room, with the help of a periscope.

Question 23.
Keep the mirrors in such a way that the angle between the mirrors is 90 degrees and observe the images and compare them with the object. What do you notice? Is there any difference between those images? Imagine the reason for that.
Answer:

1. We observe 5 images of the object .
2. The intensity of the images decreases.

Question 24.
What are spherical mirrors?
Answer:

1. We have seen the mirrors whose reflecting surfaces look like the head of a steel spoon.
2. The mirrors which contain curved reflecting surfaces are called spherical mirrors.

Question 25.
Why do we call concave and convex mirrors as spherical mirrors?
Answer:

1. Take a rubber ball and cut a portion of it with knife as shown in figure. Be careful. Ask your teacher to help you in cutting the ball).
   
2. The inner surface of the cut piece of ball is called concave surface and the outer surface of it is called convex surface.
3. If the reflecting surface of a mirror is concave, it is called a concave mirror see figure (a)
   
4. If the reflecting surface is convex, then it is called as convex mirror. See figure (b).
   
5. Any concave or convex mirror is a part of a sphere. Hence these mirrors are called spherical mirrors.

Question 26.
How is the image of a candle is seen in a mirror. Draw a diagram to explain.
Answer:

1. See the diagram below.
2. The ray of light from the candle is reflected at the mirror, and bounces off at the same angle as it come to the mirror.
   
3. Our eye does not know that the light has been reflected.
4. Our eye sees the object (the candle) in the mirror, and feels that light is coming from that candle which seems to be behind the mirror.
5. In this way we see an image of the candle.

Question 27.
Take a drawing sheet and cut it into a few pieces. Write an English letter in capitals on each piece of drawing sheet. Observe the images of the letters formed in the mirror as shown in figure.

1. Which of the images appear same as the original letter?
2. Which of them appear reversed? Why?

Repeat above activity with Telugu / Hindi / Urdu letters and also with numbers 1 to 9, then try to answer the above questions.
Answer:
This can be done by the student.

Question 28.
On the front side of ambulances, the word AMBULANCE is written like why?
Answer:

1. All vehicles should give way to an Ambulance.
2. When the driver has seen the vehicle behind it, letters written on it must be clearly visible.
3. So the letters Ambulance are written on the vehicle with lateral inversion.
4. When the image of these letters are seen in the rear mirror, they will be laterally inverted and the name Ambulance will be clearly visible to him.
5. The driver immediately gives way to that Ambulance.

Question 29.
Every day we see our image in a plane mirror. Is it a real or virtual image? How can you decide?
Answer:

1. It is a virtual image.
2. The image formed in a plane mirror cannot be caught on a screen.

Question 30.
Keep a mirror close to your face and look into it. Move the mirror backward and observe the image. What change do you observe? Try this activity using Convex, Concave mirrors. In which mirror do you get an inverted image ?At what distance does it happen?
Answer:

1. When the mirror moves by a distance of minimum 25 cm. then only we can see our image in the plane mirror.
2. If it is a concave mirror, as long as our face it with in the focus of the concave mirror a small virtual image of the face is seen.
3. When the concave mirror is at a distance beyond its focus, then the image formed will be bigger in size.
4. In the case of convex mirror a virtual, small image is formed in it when it is kept at a suitable distance form the face.

Question 31.
Why are rearview mirrors arranged for vehicles?
Answer:

1. The mirrors at both sides of driver in motor vehicles like bus, car, motor vehicles are rearview mirrors.
   
2. These are used by drivers to see vehicles which are moving behind or beside of the vehicle without turning
   their heads.

Question 32.
Take a plane mirror. Go to a vehicle. Observe your image in the rearview mirror and as well as in the plane mirror. What difference do you find?
Answer:
We have noticed that the image formed by the rearview mirror is smaller than the image in a plane mirror.

Question 33.
a) How is the image on the outer portion of the spoon?
b) How is the image on the inner portion of the spoon?
Answer:
a) The image on the outer portion of the spoon is small in size.

b) The image on the inner portion of the spoon is reversed.

Question 34.
Have you noticed the surface of reflection in a torch light or in a head light of a vehicle? What is its specialty?
Answer:

1. Observe the torch light or headlight of a vehicle.
2. We notice a concave mirror behind the bulb (see figure)
3. Due to this concave surface the brightness of a small bulb is increased.
   

Question 35.
What happens if the surface of reflection in the torch or in a head light of a vehicle is convex like in figure?

Answer:

1. The intensity of light totally decreases.
2. A convex mirror diverges the light rays.
3. So the rays of light from the bulb diverge out. Giving small intensity of light on the road.

Question 36.
How is concave mirror useful to dentists?
Answer:

1. Dentists use concave mirrors to examine our teeth (See figure).
   
2. These concave mirrors used by doctor help to see a bigger image of teeth.

Question 37.
In our daily life while we stand in front of windows we observe our images on the glass of some windows but don’t find images on the glass of some other windows. Why?
Answer:

1. Our image is clear when we stand in front of certain types of glass as shown in figure (a).
   
2. Our image is not clear when we stand in front of some other types of glass as shown in figure (b).
3. If the surface of the window glass is smooth, due to the regular reflection we are able to see our image in that glass.
4. But if the surface of the window glass is rough, due to the irregular reflection we can’t find our image or we find unclear images in that glass.

Question 38.
Observe the image of the sun or a tree in still water. Later, disturb the water by throwing a pebble. How does the image of the Sun or the tree appear now? Why?
Answer:

1. When the water is still, its surface will be smooth and regular reflection takes place on it.
2. The image of an object formed due to still water will be clear.
3. When water is disturbed, the surface of water becomes rough and irregular reflection takes palce.
4. Due to this irregular reflection the image of an object may not be formed, if formed it will not be clear.

Question 39.
How many images are formed if two mirrors are kept in 60° angle to each other?
Answer:
The angle between two plane mirrors = 60°
Number of images formed

5 images are formed.

Question 40.
Sasi asked her father to fix mirrors on her new house for elevation. But her father did not accepted. Imagine why he said like that.
Answer:

1. If we decorate the front portion of the house, accidents may happen.
2. Because sunlight falls on these mirrors and reflects back.
3. This reflected light may fall on the men and vehicles, leading to accidents.

Question 41.
You are given a mirror. How can you identify whether it is convex mirror or concave mirror?
Answer:
A)

1. If the reflecting surface of a mirror is concave, it is called a concave mirror.
2. These mirrors form real and inverted images.
3. These are used in headlights of vehicles. ENT doctors also use these mirrors for their observations.

B)

1. If the reflecting surface is convex, then it is called a convex mirror.
2. They always form erect and virtual images.
3. These are used in rear view mirrors of the vehicles.

Question 42.
The following experiment has been conducted in your laboratory.

Answer the following questions based on this.

1. Which mirror is used in this experiment?
2. How does the image of candle appear on the screen?
3. Since the image is caught on the screen, what is the name of the image?
4. What are the apparatus required to conduct this experiment?

Answer:

1. Concave mirror
2. Inverted
3. Real image
4. U-stand, mirrors, candle, matchbox, screen, scale.

Question 43.
List out the properties of a convex mirror.
Answer:
Properties of a convex mirror :

1. If the reflecting surface is convex, then it is called a convex mirror.
2. Always form erect and virtual images.
3. These are used in rear view mirrors of the vehicles.

AP State Syllabus AP Board 7th Class Science Important Questions Chapter 3 Animal Fibre

AP State Syllabus 7th Class Science Important Questions 3rd Lesson Animal Fibre

7th Class Science 3rd Lesson Animal Fibre Important Questions and Answers

Question 1.
How silk weaving began ? Write the story behind it.
Answer:

1. Chinese traditions, along with the writings of Confucius tell the same 2700 BC tale. It states that the empress Leizu (Hsi – ling – shi) was having tea one day under a mulbery tree with her husband, emperor Huang-ti, when a silk worm’s cocoon fell into her cup.
2. In an attempt to take it out, the thread of the cocoon began to unroll. So the Empress thought of weaving the thread.
3. The Emperor encouraged his wife to study the life of silk worm, and so she learned the art of raising silk worms or what is called sericulture. Her finding was taught as well and thus the advent of the silk industry.
4. However, archaeological evidences show that the origin of silk industry traces back to 3000 and 5000 BC.
5. The sites of Yangshao culture in Xia Country; Shanxi reveal a cocoon of a bombyx mori or a domesticated silk worm along with silk weaving looms.

Question 2.
Write a note on The world of wool.
Answer:
Woolen fabrics are as ancient as human civilization. According to archeological evidences domestication of woolly sheep may have started around 6000 BC by early Iranians. Earliest woven woolen garments are dated 2000 – 3000 years later. In 15th century, British made laws to control wool smuggling and at one time they punished people by cutting off their hands ! The industrial revolution introduced mass production of wool. Leaders of wool production are Australia and China.

Question 3.
What is the historical record of spinning and weaving?
Answer:
Spinning and Weaving:
The spinning of animal or vegetable fibres into thread dates from about 7000 BC, from the Middle East; the earliest tools used were a distaff (a cleft stick holding a bundle of fibres) with a weighted spindle to twist them together. The oldest known textile, from Asia Minor, dates from around 7000 BC. The first looms for weaving wool dates from about 5000 BC.

Family Scene A Hittite lady spins wool in a bas-relief from the 8th century B.C.

Question 4.
Are caterpillars dangerous?
Answer:
All caterpillars are not dangerous. Some are useful too.

Question 5.
From where do we get fibres? Explain.
Answer:

1. We get fibres from plants and animals.
2. Cotton, Jute, Gongoora, Coconut plant fibres are useful to make different kinds of fabrics.
3. In the same way we get fibres of silk and wool from animals like silk worms, sheep, goat, camel, and yak etc.

Question 6.
Who will purchase the tiny silk worms?
Answer:
Farmers from Kurnool, Kadapa, Chittoor and some other places of our state come and purchase these tiny worms.

Question 7.
Why do farmers buy silk moths ? What is the name of the centres?
Answer:

1. Sometimes farmers buy silkmoths because to produce eggs from them.
2. The eggs are produce by thermselves (by farmers) in their own centres.
3. The egg producing centres are called Grinages’.

Question 8.
Narrate the stages of transformation from egg to cocoon in the sericulture. What do you do in this process?
Answer:

1. Large tray with leaves and larva feeding on them could be seen.
2. Some trays had white and yellowish egg like structures.
3. Farmers grow silk worms to get cocoons. They get 5-6 harvests of worms in a year.
4. Farmers bought mulberry twigs from Palamaneru of Chittoor district, where sericulture (the whole process of obtaining silk starting from silk moth) is carried out.
   
5. Farmers plant the twigs to get the mulberry crop.
6. We purchased tiny white coloured silk worms (caterpillars) from seed growing centres at Horsely Hills.
7. We place these worms in trays. We chop Mulberry leaves into small pieces to feed them.
8. 
9. These worms eat leaves day and night. They need good hygienic conditions and proper light to grow.
10. When they grow biggerin size, we transfer the worms into big sized cane frames called “Chandrikalu”.
11. After 30-35 days the caterpillar stops eating and settles at a particular place. It weaves a net to hold itself.
12. Caterpillar moves its mouth from side to side and secretes fibre-like substance.
13. When it is exposed to air and heat it becomes strong.
14. The net is woven completely to cover the body of the caterpillar. This seems to be a closed sack. This is called Pattukayalu’ (Cocoon).
15. The larva of silk worm undergoes changes in the cocoon to change into a moth. After 2-3 weeks young moths come out from the cocoons and fly away.
16. So we have to be very careful. Within 2-3 days of formation fo cocoon, we start removing them from the tray.

Question 9.
How is the process of reeling, fibre to yarn is done? Describe.
Answer:

1. Some people will attend to boiling and stirring something in large pots. (Fig. )
   
2. Cocoons are being boiled in water.
3. Cocoons are boiled to get silk fibre.
4. Caterpillar of silk worm spins fibre which is mainly made up of two types of protein (sirisine and fibroin) and is very strong.
5. The cocoons have to be boiled to loosen the fibre to be able to reel it.
6. Obtaining silk fibre from cocoon is called reeling. It is done with special machines called reelers and twisters.
7. The silk fibre is carefully collected from the cocoon and nearly 3 to 18 of such threads are wound together to make yarn from it which is reeled (Fig. )
   

Question 10.
How is silk yarn woven to fabrics?
Answer:

1. The reeled yarn is cleaned, bleached and coloured.
   
2. The yarn is ready to be woven into a variety of designed fabrics, on looms.
3. We can see reeling centres at Nandikotkur, Hindupur, Dharmavaram and Madanapalli etc.

Question 11.
Describe the process of scouring of wooL Why is cool air passed over it after washing?
Answer:

1. Sheared skin with hair is dipped in such tanks and stirred with a spade.
2. Often it may be washed under a stream of water as well.
3. This water contains some chemicals to remove grease, dirt and dust.
4. This process ¡s called washing or scouring.
5. Alter washing, cool air is Passed over the wool to makes it softer.

Question 12.
Explain the process of sorting wool.
Answer:

1. People sorting coarse and soft ones as well as broken and long ones and making separate piles of them.
2. Unwanted materials like twigs or hits of leaves etc., that may he present with the wool are also separated out.
3. This process is called sorting or wool classing. Fleece is the soft mass of wool.

Question 13.
How do these woolen fibres get different colours? What is there in the tubs? Explain the process of spinning.
Answer:

1. There are beaches and dyes in the tubs. Woolen fibres are bleached and then dyed with different colours.
2. The coloured fibres are used to make yarn. These fibres are then combed.
3. There is a machine for combing or carding wool. Wool is pulled through many teeth of the combing machine (Fig. )
   
4. From there, a machine rolls and pulls it out into a thick rope and still another pulls and twists it into a long thread.
5. This is the process of spinning.
6. Flere you can see it being wound on whirling spools as well. (Fig. )
   
7. Thus we get the yarn which may be dyed before weaving.

Question 14.
What is the advantage of stiffling?
Answer:

1. Stiffling helps to store the cocoons for a long period.
   
2. This process is usually done in reeling centres.

Question 15.
Where are the cocoons sold ? In which places rfites of cocoon are usually enquired ?
Answer:

1. These cocoons are kept in sealed bags and sold at the cocoon market.
2. If not stiffled, we sell them off within a week.
3. Usually enquiries about rates of cocoons are made in the market at Hindupur, Madanapally, Dharmavaram, Kadiri, Palamaneru and Raychoti.

Question 16.
What are the different silks produced in our state ? What is tasar silk ? Where do the silk plantation is mainly concentrated?
Answer:

1. Apart from Mulberry, Tasar silk (Desali Pattu) is produced in our State.
2. Some species of silk moths that lay eggs on termanalia (oak) plantation produce tasar silk.
3. Mostly tribal people rear these kind of cocoons.
4. This silk plantation is concentrated in coastal regions of East Godavari and Visakhapatnam.

Question 17.
What are the different places famous for silk? What are the different types of silk available to us?
Answer:

1. Dharmavaram – silk city of Andhrapradesh.
2. People weave silk fabric by using silk yarn on handlooms.
3. For there people, weaving is a traditional occupation.
4. They get silk yarn from reeling centres to weave a variety of sarees.
5. Venkatagiri pattu and Dharmavaram are famous types produced by our state.
6. Dharmavaram is famous for its wide border and rich buta or dots.
7. Banaras, Kanchipuram, Dharmavaram, Narayanpet, Kothakota, Pochampally are all types of silk fabrics.
   
8. They get their names from the places where they are made.
9. We also have heard the names of tasar silk, mooga silk, kosa silk, eri silk etc.
10. These are all several varieties of silk. Some chemicals add strength to silk fibres.
11. Silk is used to make other products as well like satin and crepe. We have both handlooms and power looms to weave silk.

Question 18.
What is the difference between silk and cotton?
Answer:

Silk	Cotton
1. Mainly protein	1. Mainly a carbohydrate called cellulose

Question 19.
How are we protected from heat and cold by wool?
Answer:

1. Wool is a poor conductor of heat. Air trapped in between the woolen fibres and our body prevents the flow of heat from our body to our surroundings.
2. So we feel hot and are protected from cold.
3. Woolen cloth also helps to douse fire.
4. That is why it is good to wrap a person, who is caught in fire, with a blanket.

Question 20.
How much of yarn do we get from cocoons? How many people are involved in this process? Are they safe with this?
Answer:

1. The thread you get from the average cocoon ranges from about 1,000 to 3,000 feet, and about 2,000 to 3,000 cocoons are required to make 500 gm of silk.
2. That is about 5,000,000 feet or more than 1,000 miles!
3. That’s not all. People involved in the process suffer from skin as well as respiratory problems due to continuous handling of the silk worm and the silk fibres.

Question 21.
From where wool is obtained?
Answer:

1. Clothes like sweaters, mufflers, hats, long coats, table covers etc. are some woolen varieties.
2. There were different types of animals like sheep, goat, yak, llama, camel, alpaca etc.
3. Wool is obtained from hair of all the animals.
4. It is also called fleece or fur collectively.
5. It is mainly a protein. Good quality wool is obtained from Merino sheep.
6. They are specially reared. The fleece is 3-5 inches long and very fine and most valuable.
7. A merino sheep may yield about 5 to IS kg of wool per year.

Question 22.
Do we find any difference between hairs of all animals?
Answer:

1. Certainly, hair of camel that lives in Rajasthan is not same as Angora goat that lives in Kashmir.
2. Camels have rough and coarse hair.
3. Under this rough hair some animals usually have soft hair as well.
4. Angora goat or the Merino sheep have soft hair.

Question 23.
Where do we find sheep or goat that give us wool?
Answer:
In Jammu & Kashmir, Himachal Pradesh, Uttaranchal, Arunachal Pradesh, Sikkim, Haryana, Punjab. Rajasthan and Gujarat. They are often reared on large farms.

Question 24.
What do the people do with scissor in removing fleece of sheep?
Answer:

1. A shear is used to cut fleece from sheep.
2. During spring season fleece of sheep is removed from its body using this type of razor.
3. This process is called shearing (Fig.). To prevent damage to skin, grease is used.
   

Question 25.
If you are going to visit Ooty, a hill station in the month of November, which type of clothes would you carry
Answer:

1. Ooty is the cold place as it is a hill area.
2. I would like to keep woolen clothes in my luggage in order to protect myself from cold condition.
3. I would carry sweaters, gloves, scarfs and shoes to protect myself during cold days.

 

AP State Syllabus AP Board 7th Class Science Important Questions Chapter 6 Weather and Climate

AP State Syllabus 7th Class Science Important Questions 6th Lesson Weather and Climate

7th Class Science 6th Lesson Temperature and Its Measurement Important Questions and Answers

Question 1.
How do elders predict rain?
Answer:

1. It is a common experience for everybody to hear elder people talking about the possible weather on a day before planning to celebrate a function of the family.
2. They do it by observation of different seasons.
   
3. Farmers listen to radio or watch T.V. for weather forecast.
4. They depend on these weather predictions to plan their agricultural activities.
5. These weather predictions effect our daily life.

Question 2.
How does the meteorological department make weather predictions?
Answer:

1. The meteorological department collects data and uses it to make predictions.
2. This is about weather of Hyderabad for three consecutive days.
   
3. We find that these aspects of weather keep changing.
4. The humidity, changes, the wind changes, the temperature changes the sunrise and sunset times change too.
5. Keeping all these things in consideration the department make weather predictions.

Question 3.
What aspects do you see in the weather record?
Answer:

1. We find that there are some changes in a day. But most of the day is normal.
2. The weather is a complex phenomenon that it can vary over very short periods of time.
3. Sometimes its sunny in the morning but clouds appear from somewhere and it starts raining.
4. Within a matter of a few minutes this gives way to bright sunshine.
5. We must have had several such experiences. The temperature, humidity, rain, wind speed change.
6. All this effects the life of human beings and other living organisms. This constitutes weather.

Question 4.
Describe the construction and working of six’s maximum and minimum thermometer.
Answer:
Description – and working:

1. Six invented the maximum minimum thermometer (MMT) thermometer to measure highest and lowest temperatures of’a place.
2. This consists of a cylindrical bulb A, connected through a U-shaped tube to spherical bulb B that contains alcohol.
   
3. When the temperature increases, the alcohol in the bulb A expands.
4. The mercury in the U tube goes up to the bulb B side and the indicatorfl^also moves up.
5. This indicates maximum temperature of the day.
6. If the temperature decreases,alcohol in the bulb A contracts then the mercury in the U-tube goes to the A bulb side and the indicator (I₂ ) also moves up.
7. This indicates the minimum temperature of the day.
8. After taking readings the indicators I₂ and I₁ are brought to their original places by using a magnet.

Question 5.
How do you find the magnitude of rain fall?
Answer:

1. Take a 10cm wide beaker and insert a funnel of the same width.
2. Keep the apparatus in an open place when it is raining.
   
3. The rain water would be collected through the funnel into the beaker.
4. After the rain is over, measure the amount of water collected in the beaker.
5. If the depth of water is 1 cm then that the magnitude of rainfall is 1 cm.

Question 6.
Observe the weather report (temperature and rain fall) of two places in our state. The average temperature and rain fall for the last 25 years of the particular month is given in the table.

Answer the following questions:
a) In which month was maximum temperatures recorded? Why?
Answer:
In the month of may maximum temperatures were recorded.
b) Comparatively which place is hot? Why?
Answer:
Rentachintala is comparatively hot because the average rainfall is less compared to Arogyavaram.
c) How can you say Arogyavaram is cooler than Rentachintala in summer?
Answer:

1. In Arogyavaram, in the mid summer, the maximum temperature recorded was only 33°C as against 41°C recorded in Rentachintala.
2. So Arogyavaram is cooler than Rentachintala.

Question 7.
What is meant by climate?
Answer:

1. The average weather pattern taken over a long time, say 25 years, is called climate of that place.
2. Broadly, the same patterns of temperature, rainfall, humidity wind speed that have been generally continuing for a long time, say the last 25 years, at a place gives the climate of that place.
3. If we find that temperature at a place is generally high for large part of the year, we say the climate of that place is hot.

Question 8.
How do we compare a place which is hot with a place which is cool?
Answer:
With the help of six’s maximum and minimum thermometer we compare a place which is hot with a place which is cool.

Question 9.
How do meteorologists measure the rain fall? What are its units?
Answer:
Meteorologists measure the rainfall using a ‘Rain gauge’. It is also called Udometer or Pulviometer or Ombrometer. They can measure exact amount of rainfall. Rainfall is expressed in centimeters or millimeters.

Question 10.
Why is it sweaty in Vijayawada and relatively less in Hyderabad in summer?
Answer:

1. Even though it is hotter, we do not sweat as much in Hyderabad.
2. In places near a river or in coastal regions the weather in summer is sweaty.
3. If we are in coastal region in summer we would feel very sweaty in addition to feeling hot winds.
4. That is why Vijaywada is more humid than Hyderabad.

Question 11.
Which region on the globe is very hot and which region is very cold?
Answer:
We know that in the equatorial region it is very hot and in the polar region, it is very cold.

Question 12.
Take a newspaper or watch the TV news and record the maximum and minimum temperature, rainfall, humidity and wind pattern of any 3 cities or towns in a table. Do this over a week.
Answer:

1. Here the maximum temperature recorded over a week in Hyderabad is taken.
2. We will plot the graph.
   
3. Graph showing the variation of maximum temperature during 10-14 Dec. 2011 at Hyderabad.

Question 13.
Collect weather reports of a nearby city from newspapers. Tabulate your Observations for a week and compare them.
Answer:

1. For guidance sample tabular form is given.
2. The student has to perform this activity.
   

Question 14.
Answer the following questions from the data collected.
a) When was the maximum temperature recorded?
b) When was the minimum temperature recorded? Why?
c) Is there any similarity in temperatures between your school and the nearest city?
Answer:
a) …………………………………..
b) …………………………………..
c) …………………………………..

Question 15.
a) Pravin has measured temperature of his village with the help of MMT (Maximum, Minimum thermometer.)
b) He expressed his observations through a graph.
c) The observations are also tabulated.
d) Look into them and answer the following questions.
a) For how many days did Pravin observe the temperature of his village?
b) On which day was the highest temperature recorded?
c) On which days did the lowest temperature fall?
d) Do you find any relation between 10th and 14th of December 2011? What is that?
e) Make a graph with your observations of maximum and minimum temperatures.

Answer:
a) For five days.
b) On 2nd, 3rd, 4th and 5th days the highest temperature was recorded.
c) On the 1st day the lowest temperature fall.
d) There is an increase in temperature and the rise in temperature was maintained for four days.
e) The student can do this activity.

Question 16.
How do you find the direction of the wind? Describe an activity.
Answer:

1. Let us find the direction of wind by using card board pieces and a thin nail.
2. Take two cardboard pieces and cut them the shape of an arrow and paste them together.
   
3. Insert a thin needle or iron wire as shown the figure in the middle of the arrow.
4. The needle must be long enough to be fixed on a strong base and should allow the arrow to move along the direction of the wind.

Question 17.
With the help of an anemometer observe the directions of the wind and tabulate your observations in the table given here.

Now answer the following questions:
a) Does the wind move in the same direction the whole day?
Answer:
The student can answer this by observing the data collected by him / her.
b) In which direction does it move in the morning?
Answer:
This question also can be answered by the student.

Question 18.
What is humidity? Explain it with an activity.
Answer:
Humidity: The quantity of moisture in the air is the ’humidity’ of the place. If the humidity is high when it is hot, we feel sweaty.
Activity:

1. Take about 10 ml. of water in a test tube. Heat it on a Bunsen burner or a candle.
2. When water is heated, it changes into water vapour. The vapour enters into the air.
3. In the same way sea water changes into vapour due to heating by the sun.
4. That water vapour in the atmosphere is the humidity.

Question 19.
What happend during the tsunami in Andaman and Nicobar islands in 2004?
Answer:

1. Many people died during the tsunami in Andaman and Nicobar islands in 2004.
2. But the tribals who observed the ocean moving back and birds making sounds moved away from danger.
3. They could predict the danger and save their lives.

Question 20.
Write a weather report similar to the weather report given in Television.
Answer:

1. Isolated rain or thunder showers are lightly to occur over Chittoor, Nellore, Prakasham and some parts of Kadapa districts.
2. Mainly dry weather will prevail over southern Telangana districts and northern coastal districts of Andhra Pradesh.
3. Sky should be cloudy for the next two days in Kurnool and Ananthapur districts.

Question 20.
Describe a weather report actually given by the department.
Answer:

1. According to meteorological department report 42°C maximum temperature recorded at Ramagundam of Karimnagar district and 29°C minimum temperature recorded at Aarogyavaram of Chittore district.
2. Because of cumulonimbus clouds 2mm of rainfall was recorded in Hyderabad.
3. Scattered rainfall recorded in some parts of interior Rayalaseema.
4. Remaining part of the state was dry.

Question 21.
What is the difference between a weather forecast and a weather report?
Answer:

1. The report that explains future conditions is a weather forecast.
2. The report that explains about past conditions is a weather report.
3. In common conversation we often refer to both as weather report.

Question 22.
What are the weather components?
Answer:
Temperature, rain fall, wind speed, humidity…. etc., are the weather components.

Question 23.
How do farmers estimate the rain fall?
Answer:

1. Farmers estimate the rainfall based on the wetness of the soil after the rain.
2. They call-it as “PADUNU”.
3. This much of rainfall is sufficient to start agriculture activities like ploughing.
4. This is an approximate measure.

Question 24.
Draw the diagram of an Anemometer what is its use?
Answer:
We can measure wind speed and direction with an Anemometer.

Question 25.
Observe features of the following states, and specific places in India from an ATLAS. Try to write down something about the climate in these areas.

State	Climatic Condition
Kerala
Andhra Pradesh
Rajasthan
Jammu & Kashmir
West Bengal

Answer:
The student with the help of the teacher can write something about the climate in those areas.

Question 26.
Describe the climate of our country as per the studies of IMD.
Answer:

1. The Indian Meteorological Department (IMD) studies climate of our country.
2. Climate describes the weather condition occurring over a relatively longer period of time in a given place.
3. For example in the month of June.
4. We expect the weather to be mild in Bangalore, humid in Kolkata, hot and dry in parts of Rajasthan, cold in Kashmir and rainy in Coastal Kerala.
5. Does it mean that in coastal Kerala it is always rainy in the month of June or if it would be always humid in Kolkata?
6. Nowadays there is a complaint that climate is not as ordered as it was .
7. Seasonal climatic condition do not appear as predictable and known.

Question 27.
How do people adjust to the climate? Why in 2010 Kurnool and other parts in Rayalaseema submerged infloods?
Answer:

1. The people living in an area adjust to the conditions of climate.
2. For example the rain fall has being relatively less for the past two decades.
3. Even in Rayalaseema during rainy season the tanks and canals remain dry.
4. The dried canals and tanks are now used for other purposes.
5. The less rainfall has also led to developing ways to use less water.
6. The change in rainfall pattern shows there may be shifts in climate over long periods of time.
7. In areas which do not have a climate of rain when it rains heavily there is no way to drain out the water.
8. As a result many areas were flooded and submerged in Kurnool in 2010 and also in other parts of Rayalaseema.

Question 28.
How does climate effect our life style?
Answer:

1. Climate mostly effects on our daily life. We change our life style to suit that climate.
2. We wear cotton clothes in summer.
3. We want to drink cool water also.
4. We take care to protect ourselves from rain.
5. We take many precautions we need to take if we were going to visit Kashmir or Ooty during winter.

Question 29.
a) The students of Sanjamala village collected the information about the temperature of their village in 5 days and reported in the table. Observe the table.

Date	Minimum Temperature	Maximum Temperature
0101-2018	20°C	32°C
02-01-2018	19°C	33°C
03:01-2018	20°C	32°C
04-01-2018	20°C	32°C
05-01-2018	18°C	31°C

Answer the following questions:
i) On which day was Maximum Temperature recorded?
ii) On which day was Minimum Temperatrue recorded?
iii) What is the average Minimum Temperature of 5 days?
iv) What changes did you observe in the Temperature?
b) Draw a graph based on the information in the table.
Answer:
a) i) 02-01-2018
ii) 05-01-2018
iii) 19°C
iv) Lowest and highest temperatures.
b)

Question 30.
What aspects should you observe to predict the weather of your village, by watching sky?
Answer:
The time of sunrise and sunset, wind flow, percentage rainfall in that area should be taken into consideration to estimate the type of weather in that given area.

Question 31.
Table showing the variation of maximum and minimum temperature during the period between 10 and 14 September 2017 at Guntur. Based on this draw a graph.
Answer:

Question 32.
Observe the table and write answers for the following questions.

Month	Temperature	Rainfall
May	48°C	0 mm
July	39°C	7 mm
October	37° C	10 mm
November	34°C	15 mm

i) This table indicates ………….
ii) In which month was maximum rainfall recorded?
iii) Least temperature was recorded in which month?
iv) Why is maximum temperature recorded in the month of May?
Answer:
i) The above table tells us about the temperature and rainfall from May to November.
ii) November.
iii) November.
iv) Because May falls in summer.

Question 33.
Observe the below table and write answers for the following questions.

Weather	Day 1	Day 2	Day 3
Maximum temperature	28°C	27°C	29°C
Minimum temperature	21 °C	17°C	21°C
Rainfall	None	Light shower	None
Sky may be	Clear	Cloudy	Cloudy
Wind	Very mild breeze	Mild breeze	Good breeze
Humidity	95%	90%	85%
Sunrise	6.25 a.m.	6.30 a.m.	6.31 a.m.
Sunset	5.40 p.m.	5.40 p.m.	5.41 p.m.

i) What aspects did you see in the weather record?
ii) Rainfall was recorded on which day?
iii) On which day was maximum temperature recorded?
iv) Among these three days, long day is observed on?
Answer:
i) Maximum temperature, minimum temperature, rainfall, sky, air, humidity, sunrise, and sunset.
ii) Second day
iii) Third day
iv) First day

Question 34.
Observe the diagram and answer the following questions.

i) What is the name of the apparatus in the picture?
ii) Name the liquid present in bulb – A.
iii) Name the liquid present in U-shaped tube.
iv) How is it useful in daily life?
Answer:
i) Six’s maximum minimum thermometer
ii) Alcohol
iii) Mercury
iv) To measure the maximum and minimum temperature of a day.

Question 35.
Observe the graph showing rainfall of a place from August to December. Write down the observations from it and answer the following questions.

i) Name the month in which minimum rainfall was recorded.
ii) Name the month in which maximum rainfall was recorded.
iii) Name the months in which less than 50 mm rainfall I was recorded.
iv) In which months was the rainfall recorded more than 50 nun?
Answer:
i) September.
ii) November.
iii) August, September and October.
iv) November and December.

Question 36.
Ritwik observed the temperature of his village and drew the following graph Analyse the graph and answer the following questions.

a) How many days does Ritwik observe temperature?
b) On which day the lowest temperature is recorded?
c) In which days does the temperature remain same?
d) What apparatus is used to measure the temperature?
Answer:
a) 5 days.
b) First day
c) 2nd, 3rd, 4th and 5th days.
d) Six’s maximum-minimum thermometer.