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These AP 7th Class Science Important Questions 4th Lesson Respiration and Circulation will help students prepare well for the exams.

AP Board 7th Class Science 4th Lesson Important Questions and Answers Respiration and Circulation

Question 1.
What is inspiration?
Answer:
The process of inhaling air is called inspiration.

Question 2.
What is expiration?
Answer:
The process of exhalation of air is called expiration.

Question 3.
What is respiratory rate?
Answer:
The number of times we inhale and exhale air in a minute is called the Respiratory Rate.,

Question 4.
What is the normal respiratory rate in human beings?
Answer:
The normal respiratory rate in human beings is 14 to 20 times per minute.

Question 5.
What are the only part of the human body which floats on water?
Answer:
Lungs are the only part of the human body which floats on water

Question 6.
What does our circulatory system consisting of?
Answer:
Circulatory system consists of Heart, Blood vessels and Blood

Question 7.
What is the pumping organ in the blood circulatory system.
Answer:
Heart is the pumping organ in the blood circulatory system.

Question 8.
How many chambers are there in the human heart? What are those?
Answer:
Human heart has four chambers, upper two chambers are called Atria and lower two chambers are called Ventricles.

Question 9.
What is heartbeat?
Answer:
The rhythmic contraction followed by its relaxation of heart is called heartbeat.

Question 10.
What is the instrument used to feel and measure the “heart beat?
Answer:
Stethoscope is the instrument used to feel and measure the heart beat.

Question 11.
What is the role of circulation in the human body?
Answer:
The process of circulation helps in the supply of digested food and oxygen to all parts of the body (cells) and also to bring back the waste material.

Question 12.
What is the fluid portion of the blood?
Answer:
Plasma is the fluid portion of the blood.

Question 13.
What are the different types of blood cells in the human blood?
Answer:
Blood cells are of three types – Red blood cells, White blood cells and Blood platelets.

Question 14.
Which blood cells act like police force of our body?
Answer:
White blood cells act like police force of our body.

Question 15.
Why red blood cells are red in colour?
Answer:
Red blood cells have a colouring pigment called Haemoglobin. It gives blood the red colour.

Question 16.
What is the function of haemoglobin?
Answer:
Haemoglobin acts as a carrier for oxygen and carbon dioxide and plays a key role in respiration. ,

Question 17.
What is the function of Blood platelets?
Answer:
Blood platelets play an important role in coagulation of blood when there are cuts and wounds.

Question 18.
Which organisms have colour less blood?
Answer:
Insects like cockroach have colour less blood.

Question 19.
Give examples for the organisms having blue coloured blood?
Answer:
Prawns, snails and crabs have blue coloured blood.

Question 20.
Expand NCDs.
Answer:
Non communicable diseases

Question 21.
Give some examples for non-communicable diseases.
Answer:
Heart attack, Cancer, Paralysis

Question 22.
What are the major causes for non-communicable diseases?
Answer:
Tobacco and alcohol use, poor eating habits, and lack of exercise are the major causes for non – communicable diseases.

Question 23.
What is immunity?
Answer:
Immunity is the inbuilt capacity of the body to fight and overcome the effects of disease causing germs.

Question 24.
What is meant by infection?
Answer:
The entry of disease-causing germs into our body to grow and multiply is called infection.

Question 25.
Expand SARS.
Answer:
Severe Acute Respiratory Syndrome

7th Class Science 4th Lesson Respiration and Circulation Short Questions and Answers

Question 1.
What is breathing? Explain brifly about breathing.
Answer:

1. The process of inhalation and exhalation of air is called Breathing.
2. During the process of inhalation the air with more oxygen and less carbon dioxide enters the lungs through nostrils.
3. During the process of exhalation the air with more carbondioxide and less oxygen is sent out from the lungs.

Question 2.
Write about lungs.
Answer:

1. Lungs are pink in colour spongy, elastic and sac like structures with many tiny air sacs.
2. They are placed safely in the ribcage formed by ribs in the chest cavity.
3. The right lung is slightly larger than the left one. ‘
4. The lungs do not possess muscles, so they cannot expand or contract on their own.

Question 3.
Why is the right lung larger than the left lung?
Answer:

1. Lungs are located in the chest cavity.
2. Heart is also present in the chest cavity on the left side.
3. So, there is less space for the left lung in the chest cavity.
4. As a result left lung is smaller with two lobes when compared with the right lung which had three lobes.

Question 4.
What is diaphragm? what is its role?
Answer:

1. A large thin muscular sheet called diaphragm is attached to the lower side of the ribcage and forms the floor of the chest cavity.
2. The process of breathing involves the movement of the diaphragm and the ribcage.
3. During inhalation diaphragm moves down as a result air enters the lungs.
4. During exhalation diaphragm moves back as a result air goes out of the lungs.
5. It play major role in the respiratory movements of men when compared with women.

Question 5.
Draw the flow chart air passage in respiration.
Answer:

Question 6.
What are plants respiratory organs?
Answer:

1. Plants being living organisms, have to breathe to survive. ,.
2. Plants take in oxygen and leave out carbon dioxide, as in any other living organisms.
3. The process of breathing takes place with the help of small openings in the leaves called stomata and in stem called lenticels.
4. The roots also need oxygen to produce energy, so they absorh the oxygen present in the air spaces between soil particles with the help of root hairs.

Question 7.
What is the need to plant more trees?
Answer:

1. Plants take in Oxygen and give out Carbon dioxide during respiration.
2. The same plants take in carbon dioxide and give out oxygen during the process of Photosynthesis.
3. So we should protect and plant more trees for a rich supply of oxygen.

Question 8.
What is the role of respiration?
Answer:

1. During the process of Respiration oxygen is absorbed and carbon dioxide is sent out of the body.
2. The process of respiration leads to the production of energy in all the living organisms.
3. Respiration takes place uninterrupted even when we are sleeping, eating, working or at rest.
4. Respiration takes place without our knowledge and effort and is very much essential for the survival of the organism.

Question 9.
How can we. prevent Covid-19?
Answer:
The best way to prevent and slow down spread is

1. Protecting ourselves by washing hands with soap or sanitizer
2. Not touching the face, eyes, nose, mouth
3. Wearing a facemask Maintaining social distance
4. Strictly adhering to covid protocol SMS – SANITISE, MASK, SOCIAL DISTANCE.

Question 10.
Write the differences between bacterial and viral disease.
Answer:

Question 11.
What is sneezing? When is it occur?
Answer:

1. The process of sudden uncontrolled expulsion of air through the nose by the lungs, due to irritation in the nasal passage is called Sneezing.
2. Sneezing occurs when we inhale air with dust, smoke, pollen or strong smells.

Question 12.
What is yawning? How is it caused?
Answer:

1. The uncontrolled action of opening of our mouth wide, to take a long, deep breath of air is called Yawning.
2. It is seen when a person is bored, stressed, feeling sleepy or very tired.
3. Yawning is caused when the respiratory rate gets slowed down resulting in insufficient supply of oxygen to the brain.
4. To overcome this situation, the body goes for the involuntary opening of the mouth to take in a long deep breath of air.

Question 13.
What is coughing? When does it happen?
Answer:

1. Coughing is the result of forceful contraction of the lungs to send out the unwanted substances through the mouth.
2. This happens when some strong smells or dust irritate the inner lining of the lungs.
3. By coughing the accumulated solid and semi -solid wastes in the lungs due to cold and other related respiratory disorders are also expelled out.

Question 14.
What is Deglutition apnea? What is its importance?
Answer:

1. The temporary arrest of respiration is called Apnea.
2. Deglutition or swallowing apnea occurs reflexly when the food is in the pharynx.
3. This process prevents the food from entering into the windpipe.
4. If food enters the windpipe it will have serious effects, so the larynx moves up to stop the food from entering the windpipe. Hence we should not talk while eating.

Question 15.
When do bleeding occurs? What is the first aid foe it?
Answer:

1. Bleeding takes place when we are injured or there is a cut,
2. First the bleeding injury is to be washed with clean water.
3. Use cotton or a cloth to clean the injured are ‘
4. Then use cotton or a bandage cloth to cover the injury to stop the flow of blood.
5. Take the injured person to the nearest Doctor or Hospital if bleeding does not stop.

7th Class Science 4th Lesson Respiration and Circulation Long Questions and Answers

Question 1.
Which of the following statements are wrong? Give reasons.
1) There is no har m in trying a cigarette once, because one can stop after that.
2) One cigarette a day does not harm any more.
3) Will power alone can help a smoker to stop smoking.
4) Smoking helps you feet good and relaxed.
5) Smoking is not harmful to health.
Answer:

1. Wrong. Because almost all smoker starts by trying just once but it will become a habit hard to leave.
2. Wrong. Because every cigarette you smoke is doing damage to your body, which ultimately causes heartattack, stroke and lung diseases.
3. Wrong. Because along with will power, the love and support of the family and friends combined with medical arid psychological treatment also needed to quit smoking.
4. Wrong. Because smoking may make you feel relaxed temporarily but the long term harmful effects will affect your health, wealth and life style.
5. Wrong. Because smoking leads to several health problems such as Lung Cancer, Tuberculosis and other respiratory disorders. So, never try to start smoking.

Question 2.
Describe the structure of human heart.
Answer:

1. Heart is the pumping organ in the blood circulatory system.
2. It’s about the size of one’s fist.?
3. It is located in the centre of the chest cavity slightly bent towards the left.
4. It has four chambers, upper two chambers are called Atria and lower two chambers are called Ventricles.
5. The walls of the chambers are made of muscles which contract and relax, regularly and rhythmically to pump the blood.

Question 3.
How do you prove the aerobic respiration?
Answer:
Aim: To prove the aerobic respiration.

Apparitors : Wide-mouthed bottle, lid, sprouting seeds, beaker, lime water.

Procedure:

1. Take a wide mouthed bottle and place a handful of sprouting seeds in it.
2. Prepare some fresh lime water in a small container and place it carefully in one corner of the bottle.
3. Close the cap of the bottle and apply vaseline on the edges to make it air-tight.
4. Leave the apparatus undisturbed for a day or two days.
5. After two days open the cap and carefully take out the lime water container and observe the changes.

Observation:
The lime water turns into milky white.

Conclusion:
Lime water turned milky white by carbon dioxide, which is released by germinated seeds through aerobic respiration

Prove:
It is proven that carbon dioxide is released in aerobic respiration

Question 4.
What are blood vessels? Write about different types of blood vessels in human body.
Answer:

1. The tube like structures through which blood flow in the human body are called blood vessels.
2. There are three types of blood vessels in the human body. 1. Arteries, 2. Veins and 3. Blood capillaries –
3. Arteries carry blood with more oxygen from heart to body parts.
4. Veins carry blood with more carbon dioxide from the body parts to the heart.
5. Blood capillaries which are very thin narrow blood vessels that connect the arteries with the veins and distribute the blood to the body parts.

Question 5.
Write about composition and functions of blood.
Answer:

1. Human blood is composed of Blood cells and plasm. Plasma is the fluid portion of the blood.
2. Blood cells are of three types – Red blood cells, White blood cells and Blood platelets.
3. White blood cells are again of different types.
4. The white blood cells boost our immunity and protect us from the harmful, disease causing micro organisms that enter into our body.
5. They act like police force of our body.
6. Red blood cells have a colouring pigment called Haemoglobin in the RBC, which gives blood the red colour.
7. Haemoglobin acts as a carrier for oxygen and carbon dioxide and plays a key role in respiration.
8. Blood platelets play an important role in coagulation of blood when there are cuts and wounds.
9. Blood plays an important role in the transport of materials in animals.
10. Blood is the medium to carry the digested food materials and the inhaled oxygen to all parts of the body.

Question 6.
What preventive measures will you suggest to be healthy, strong and disease free in the context of covid 19.
Answer:

1. Protecting ourselves by washing hands with soap or sanitizer,
2. Not touching the face, eyes, nose, mouth
3. Wearing a face mask
4. Maintaining social distance
5. Strictly adhering to covid protocol SMS – SANITISE, MASK, SOCIAL DISTANCE.
6. Taking steam inhalation twice a day.
7. Drinking hot milk mixed with turmeric,
8. Taking meals when hot,
9. Taking a nutritive balanced diet,
10. Practicing breathing exercises and yoga,
11. Gargling with warm water and Taking vitamin C

Question 7.
What is Choking? What is the first aid for it?
Answer:

1. Choking occurs when the wind pipe is obstructed by an object leading to blocking of air.
2. Choking has to be attended immediately as it is dangerous.
3. In adults, hold the person from behind around the abdomen just below the ribs.
4. Press quickly and repeatedly until the person gets relief by coughing or vomiting.
5. In case of children who usually put seeds, coins or bottle caption their mouth and get choked.
6. The child should be made to lie down upside down in the lap of an adult.
7. Then, the part of the back between the shoulder bones has to be tapped strongly until the object comes out.
8. Take him to the doctor immediately.

AP Board 7th Class Science 4th Lesson 1 Mark Bits Questions and Answers Respiration and Circulation

I. Multiple Choice Questions

1. In which process accumulated semisolid wastes come out?
A) Sneezing
B) Yawning
C) Coughing
D) Apnea
Answer:
C) Coughing

2. Which of the following is occured when food enters in the wind pipe?
A) Sneezing
B) Yawning
C) Coughing
D) Apnea
Answer:
D) Apnea

3. First aid for bleeding is
A) Create pressure on the diaphragm
B) Cover with bandage
C) Upside down
D) Above all
Answer:
B) Cover with bandage

4. Which of the following requires oxygen?
A) Aerobic respiration
B) Anaerobic respiration
C) Both A & B
D) None
Answer:
A) Aerobic respiration

5. The process of inhaling air is called
A) Breathing
B) Inspiration
C) Expiration
D) Respiration
Answer:
B) Inspiration

6. The opening of the nose is called
A) Nostrils
B) Nasal cavity
C) Pharynx
D) wind pipe
Answer:
A) Nostrils

7. Inspiration occurs due to
A) Ribcage move upward
B) Diaphragm move upward
C) Air enters the lungs
D) A & B
Answer:
A) Ribcage move upward

8. Quantity of nitrogen present in the inhaled air …………%.
A) 21
B) 25
C) 78
D) 0.4
Answer:
C) 78

9. Quantity of water vapour in exhaled air 0.4 …………%.
A) 15
B) 4
C) 78
D) 3
Answer:
D) 3

10. This gas turns lime water into milky white
A) Oxygen
B) Hydrogen
C) Carbon dioxide
D) Nitrogen
Answer:
C) Carbon dioxide

11. Find the correct statement
i) In the lungs, Carbon dioxide from the inhaled air is absorbed by the blood vessels present in the lungs.
ii) Oxygen collected by the blood vessels from all parts of the body enters into the Lungs.
A) both are correct
B) i only correct
C) ii only correct
D) both are wrong
Answer:
D) both are wrong

12. This will help to quit smoking.
A) Will power
B) support of the family and friends
C) medical and psychological treatment
D) All the above
Answer:
D) All the above

13. Nicotine is present in this leaf
A) Neem
B) Pipal
C) Tobacco
D) Betel
Answer:
C) Tobacco

14. Find the odd one
A) Grasshopper
B) Cockroach
C) Earthworm
D) Honey bee
Answer:
C) Earthworm

15. Frogs respires through
A) Lungs
B) Skin
C) Tracheae
D) Both A & B
Answer:
D) Both A & B

16. Fish respire through
A) Gills
B) Skin
C) Lung
D) Both A & B
Answer:
A) Gills

17. Marine animal that respire through lung is
A) Fish
B) Dolphins
C) Prawn
D) Star fish
Answer:
B) Dolphins

18. Respiration in plants occurs through
A) Stomata
B) Lenticles
C) Root hairs
D) All the above
Answer:
D) All the above

19. Honey bee : Tracheae :: Earth worm : ?
A) Gill
B) Lung
C) Skin
D) None of, these
Answer:
C) Skin

20. In this process, energy released in our body
A) Photosynthesis
B) Digestion
C) Respiration
D) Circulation
Answer:
C) Respiration

21. This process helps in the supply of digested food and oxygen to all parts of the body
A) Digestion
B) Circulation
C) Excretion
D) Photosynthesis
Answer:
B) Circulation

22. This is not a part of circulatory system ….
A) Lungs
B) Heart
C) Blood vessels
D) Blood
Answer:
A) Lungs

23. Upper two chambers of the heart are called
A) Arteries
B) Ventricles
C) Atria
D) Veins
Answer:
C) Atria

24. The fluid portion of the blood is
A) RBC
B) WBC
C) Blood platelets
D) Plasma
Answer:
D) Plasma

25. They protect us from the harmful, disease causing micro organisms that enter into our body.
A) RBC
B) WBC
C) Blood platelets
D) Plasma
Answer:
B) WBC

26. They play an important role in coagulation of blood…….
A) RBC
B) WBC
C) Blood platelets
D) Plasma
Answer:
C) Blood platelets

27. They plays a key role in respiration.
A) RBC
B) WBC
C) Blood platelets
D) Plasma
Answer:
A) RBC

28. Which of the following does not have blue coloured blood
A) Prawns
B) Snails
C) Cockroach
D) Crabs
Answer:
D) Crabs

29. This life processes play an important role in release of energy in organisms.
A) Digestion
B) Respiration
C) Circulation
D) All the above
Answer:
A) Digestion

30. Which of the following is not a non communicable diseases?
A) Heart attack
B) COVID – 19
C) Cancer
D) Paralysis
Answer:
B) COVID – 19

31. Identify the bacterial disease
A) Common cold
B) Polio
C) Tuberculosis
D) HIV
Answer:
C) Tuberculosis

32. Identify the viral, disease
A) Typhoid
B) Common cold
C) Cholera
D) Tuberculosis
Answer:
B) Common cold

33. SMS protocol is for this disease
A) Polio
B) COVID
C) Cancer
D) Paralysis
Answer:
B) COVID

34. This is caused due to insufficient supply of Oxygen to the brain.
A) Coughing
B) Sneezing
C) Deglutition
D) Yawning
Answer:
D) Yawning

35. This process prevents the food from entering into the windpipe.
A) Coughing
B) Sneezing
C) Deglutition
D) Yawning
Answer:
C) Deglutition

36. This occurs when the wind pipe is obstructed by an object leading to blocking of air….
A) Coughing
B) Sneezing
C) Deglutition
D) Choking
Answer:
D) Choking

II. Fill in the blanks

1. COVID -19 is caused by a virus called …………………… .
2. SARS means …………………… .
3. Giving assistance before a doctor attending is called …………………… .
4. The temporary arrest of respiration is called …………………… .
5. The process of inhalation and exhalation of air is called …………………… .
6. The process of inhaling air is called …………………… .
7. The process of exhalation of air is called …………………… .
8; The number of times we inhale and exhale air in a minute is called the
9. We breathe about …………………… times per minute normally.
10. One inhalation and one exhalation together called one
11. …………………… is the first part of the Wind pipe.
12. …………………… is the process which helps in the release of energy in our body.
13. …………………… are the respiratory organs in human beings.
14. The …………………… lung is slightly larger than the …………………… one.
15. Wind pipe is kept in its shape by …………………… .
16. Lungs are protected by …………………… .
17. …………………… is the thin muscular sheet attached to the lower side of the ribcage.
18. …………………… forms the floor of the chest cavity.
19. …………………… play key role in the respiratory movements in man.
20. …………………… play key role in the respiratory movements in woman.
21. …………………… are the only part of the human body which floats on water
22. …………………… is the gas produced in photosynthesis.
23. Percentage of carbon dioxide in the inhaled air is …………………… .
24. Percentage of oxygen in the inhaled air is …………………… .
25. Percentage of carbon dioxide in the exhaled air is …………………… .
26. Percentage of oxygen in the exhaled air is …………………… .
27. Lime water turns milky white when it reacts with …………………… .
28. Glucose + Oxygen → …………………… + water + Energy
29. Tobacco smoke contains a highly dangerous substance called
30. …………………… respiration is present in insects.
31. Breathing through the skin is called …………………… respiration.
32. Respiration carried out by gills is called …………………… .
33. Respiration through is called Pulmonary respiration.
34. Plants respire through on the leaf and on the stem.
35. …………………… is the pumping organ in the blood circulatory system.
36. Upper two chambers of the heart are called and lower two chambers are called …………………… .
37. The rhythmic contraction followed by its relaxation of the heart is called …………………… .
38. Heart beat can be felt and measured by an instrument called …………………… .
39. …………………… carry blood with more oxygen from heart to body parts.
40. …………………… carry blood with more carbon dioxide from the body parts to the heart.
41. …………………… connect the arteries with the Veins
42. …………………… is the fluid portion of the blood.
43. …………………… act like police force of our body.
44. Red blood cells have a colouring pigment called …………………… .
45. …………………… acts as a carrier for oxygen and carbon dioxide in blood.
46. …………………… play an important role in coagulation of blood …………………… .
47. Blood present in cockroach is
48. …………………… is the storage point for undigested food.
49. Blood in snails is …………………… in colour.
50. …………………… was the new disease that created a global impact recently.
51. …………………… is the inbuilt capacity of the body to fight and overcome the effects of disease-causing germs.
52. The entry of disease-causing germs into our body is called ……………… .
53. COVID-19 virus spreads primarily through …………………… of infected person.
Answer:

1. SARS CoV – 2
2. Severe Acute Respiratory Syndrome
3. First aid.
4. Apnea
5. breathing
6. inspiration
7. expiration
8. Respiratory Rate
9. 14 to 20
10. breath
11. Larynx
12. Respiration
13. Lungs
14. right
15. C Shaped rings
16. ribcage
17. Diaphragm
18. Diaphragm
19. Diaphragm
20. Ribcage
21. Lungs
22. Oxygen
23. 0.04%
24. 21%
25. 4%
26. 15%
27. carbon dioxide
28. Carbon dioxide
29. Nicotine
30. Tracheal
31. cutaneous
32. branchial respiration
33. lungs
34. stomata, lenticels
35. Heart
36. atria, ventricles
37. heartbeat
38. Stethoscope
39. Arteries
40. Veins
41. Blood capillaries
42. Plasma
43. White blood cells
44. Haemoglobin
45. Haemoglobin
46. Blood platelets
47. colourless
48. Rectum
49. bluish
50. COVID-19
51. Immunity
52. infection
53. droplets of saliva or nasal discharges

III. Match the following

1.

Answer:

2.

Answer:

3.

Answer:

4.

Answer:

Do You Know?

→ Lungs are the only part of the human body which floats on water.

→ The efforts of scientists like Von Helmont and Joseph Black led to the discovery of carbon dioxide. Joseph Priestley and Lavoiser discovered Oxygen.

→ Whales, Dolphins, Seals etc. are marine animals which live in water but have lungs. So, they come up regularly ones the surface to breathe the air.

→ Plants take in Oxygen and give out Carbon dioxide during respiration. The same plants take in carbon dioxide and give out oxygen during the process of Photosynthesis. So we should protect and plant more trees for a rich supply of oxygen.

These AP 7th Class Science Important Questions 3rd Lesson Nutrition in Organisms will help students prepare well for the exams.

AP Board 7th Class Science 3rd Lesson Important Questions and Answers Nutrition in Organisms

Question 1.
Plants are also organisms. What is the food for them?
Answers:
Plants also need food like carbohydrates. But they prepare their own food.

Question 2.
How do plants get their food?
Answer:
Plants take carbon dioxide from air, water from soil, light energy from sun light and prepare their own food by using chlorophyll present in its green parts.

Question 3.
What is nutrition?
Answer:
The process of intake and utilization of food by organisms is called nutrition.

Question 4.
What are the different types of nutritions?
Answer:
Nutrition is of two types. 1) Autotrophic nutrition and 2) Heterotrophic nutrition

Question 5.
What is autotrophic nutrition?
Answer:
The mode of nutrition in which organisms make food by themselves is called autotrophic nutrition.

Question 6.
What is heterotrophic nutrition?
Answer:
The mode of nutrition in which organisms depend on other organisms for food is called heterotrophic nutrition.

Question 7.
Do all plants Autotrophs?
Answer:
No, there are some heterotrophic plants like cuscuta.

Question 8.
What kind of nutrition is seen in mush rooms?
Answer:
Saprophytic nutrition is seen in mushrooms.

Question 9.
What kind of nutrition is seen in animals?
Answer:
Heterotrophic nutrition is seen; in animals.

Question 10.
What is chlorophyll? Where is it present?
Answer:
Green coloured pigment present in plants is called Chlorophyll. It is present in the chloroplast of the plant cell.

Question 11.
What are the raw materials required for the preparation of food by green plants?
Answer:
Carbon dioxide, water, sunlight and chlorophyll.

Question 12.
Which gas is taken by plants during photosynthesis?
Answer:
Plants take carbon dioxide during photosynthesis.

Question 13.
Name the food material formed in plants.
Answer:
Glucose/ Carbohydrate is the food material formed in plants.

Question 14.
Where do photosynthesis happens in plants?
Answer:
Photosynthesis happens in the chloroplast of the green plants.

Question 15.
What is the role of chlorophyll in photosynthesis?
Answer:
Chlorophyll captures the energy of the sunlight. This energy is used to synthesise • food from carbon dioxide and water dhfihg photosynthesis.

Question 16.
Do the plants with red and brown coloured leaves perform Photosynthesis?
Answer:
Red and brown coloured leaves also have chlorophyll. The iiarge artidunt of ired, brown and other pigments mask the green colour So photosynthesis takes place in these leaves also.

Question 17.
What is chlorophyll?
Answer:
The green parts of plant contain a colouring pigment called chlorophyll.

Question 18.
What are Stomata?
Answer:
Stomata are the small openings present on the lower surface of the leaf through which gaseous exchange takes place.

Question 19.
What is the food formed in the plants?
Answer:
Plants form sugars first during the photosynthesis. Later it is converted into starch and stored in the plant body.

Question 20.
What are micro nutrients?
Answer:
Nutrient elements required in minute quantities to the plants are called micro nutrients.

Question 21.
What is saprophytic nutrition?
Answer:
The mode of nutrition in which organisms take in nutrients in the form of solution from dead and decaying matter is called saprophytic nutrition.

Question 22.
Give examples for saprophytes.
Answer:
Certain microorganisms such as bacteria and fungi like mushrooms, bread mould are ‘ the examples for saprophytes.

Question 23.
How do saprophytes help us?
Answer:
Saprotrophs grow on the dead bodies, decompose them ancl mix them With the soil. Thus thay help us by cleaning the earth surface by removing the dead and decaying matter.

Question 24.
Give one example for parasitic plant.
Answer:
Cuscuta/Dodder plant

Question 25.
Give one example for parasitic animal.
Answer:
Intestinal worms

Question 26.
Give one example for symbiotic nutrition.
Answer:
lichens.

Question 27.
What is a host in parasitism?
Answer:
Organism that provide food and shelter to the parasite is called host.

Question 28.
What is parasite?
Answer:
Parasite is an organism which grow on /in the body of another organism (host) and get food from it.

Question 29.
When do we observe National Deworming Day? What is its aim?
Answer:
Every year February 10 and August 10 are observed as the National Deworming Day (NDD). The day aims at eradicating intestinal worms among children in the age group of 1-19 years. On this day, Albendazole tablet (deworming drug) is administered to children.

Question 30.
DO we have any structures like vacuole in our body? Where do the food eaten by us go?
Answer:
We don’t have vacuole’ like structures in our body instead we have a long tubular digestive tract/ alimentary canal. The food eaten by us go in to this digestive system to get digest and absorb into the body.

Question 31.
How many chambers are there in the stomach of ruminants? What are those?
Answer:
Ruminants have four chambers in stomach. They are rumen, reticulum, omasum and abomasum.

Question 32.
What is cud?
Answer:
Partially digested food in the rumen of grass eating animals is called cud.

Question 33.
What is rumination?
Answer:
The process of bringing back the cud in to the mouth in small lumps chews it again is called rumination.

Question 34.
What are ruminants?
Answer:
Grass eating animals that performs the rumination are called ruminants.

Question 35.
How do cellulose get digest in the ruminants?
Answer:
In ruminants,, the cellulose of the food is digested by the action of certain bacteria present in the rumen of grass eating animals.

Question 36.
What is enamel?
Answer:
Enamel is the outermost layer of teeth. It is the hardest material in the human body.

Question 37.
What is tooth decay?
Answer:
Damage of enamel on the tooth due to action of acids in the mouth is called tooth decay.

Question 38.
What are the major culprits of tooth decay?
Answer:
Chocolates, sweets, soft drinks and other sugar products are the major culprits of tooth decay.

Question 39.
Where do the process of digestion starts in our body?
Answer:
The process of digestion starts in the buccal cavity in our body.

Question 40.
Where do the process of digestion completes in our body?
Answer:
The process of digestion completes in small intestine.

Question 41.
What absorbs the digested food from our digestive track?
Answer:
Finger-like out growths called villi present in the small intestine absorbs the digested food from our digestive track.

Question 42.
Through which part undigested food is sent out of our body?
Answer:
Undigested food is sent out of our body through the anus.

Question 43.
What are the common problems associated with the digestive track?
Answer:
The most common problems associated with the digestive tract are diarrhoea, constipation, irritable bowel syndrome, acidity, etc.

Question 44.
What do you understand from the given picture?

Answer:
From the given picture, I understand that skipping meals, stress, strain, cool drinks, junk food, consumption of alcohol and tobacco products are not good for our health especially to our digestive system.

7th Class Science 3rd Lesson Nutrition in Organisms Short Questions and Answers

Question 1.
Why are leaves green in colour?
Answer:

1. Leaves are green as they have chloroplasts.
2. Chloroplasts are the special structures present only in plant cells and absent in animal cells.
3. These chloroplasts consisting of a green coloured pigment called chlorophyll in them.
4. This chlorophyll is responsible for all this greenery and play key role in preparation of food.

Question 2.
How can you confirm the occurrence of photosynthesis in a plant?
Answer:

1. Glucose formed in photosynthesis is converted and stored in the form of starch.
2. So, the presence of starch in leaves indicates the occurrence of photosynthesis.
3. It can be confirmed by testing the leaf extract with Iodine solution.

Question 3.
Why leaves are called “food factories of plants”.?
Answer:

1. Plants get carbon dioxide from air, water from soil, and energy from sunlight for synthesis of their food.
2. The synthesis of food occurs in all green parts of plant body.
3. These green parts contain a colouring pigment called Chlorophyll.
4. It is more in leaves so leaves are called as “food factories of plants”.

Question 4.
Prepare a table comparing the method of our food preparation with that of plants.
Answer:

Question 5.
How do the raw materials; required for photosynthesis reach the leaf?
Answer:

1. Carbon dioxide required for photosynthesis enters into the leaf through the stomata.
2. Water absorbed by the roots transported to the leaf through the stem.
3. Leaf get sunlight when it exposed to the sun.
4. Chlorophyll is present with the leaf.

Question 6.
What is the importance off sunlight in photosynthesis?
Answer:

1. Sun light is the source of energy in the process of photosynthesis.
2. The solar energy is captured by the leaves and stored in the plant in the form of food.
3. Thus, sun is the ultimate source of energy for all living organisms.

Question 7.
Write a short note on insectivorous plants.
Answer:

1. There are some plants that eat insects.
2. Being green in colour, they can manufacture their own food.
3. But as they grow in areas deficient in nitrogen, they meet their nitrogen requirements from insects.
4. Leaves of these plants are specially modified to trap insects.
5. Nepenthes, droseras, Utricularia (bladderwort), Venus fly trap (Dionaea) are examples of some such insectivorous plants.
6. These are also called as carnivorous plants.

Question 8.
Write a short note on saprophytic nutrition.
Answer:

1. Some organisms grow on dead and decaying matter.
2. They secrete digestive juices on it convert it into a solution and then absorb the nutrients from it.
3. This mode of nutrition in which organisms take in nutrients in the form of solution from dead and decaying; matter is called saprophytic nutrition.
4. Generally we see this saprophytic nutrition in certain microorganisms such as bacteria and fungi like mushrooms, bread mould etc.

Question 9.
Write a short note on symbiosis.
Answer:

1. Some plants of the Dal family (legume plants) posses a type of bacteria growing on their roots in nodules.
2. The bacteria fixes nitrogen for the plant while it gets shelter in the roots of these plants.
3. Such an association is beneficial to both groups and called symbiosis.
4. In organisms called lichens, a chlorophyll-containing partner, which is an algae, and a fungus live together.
5. The fungus provides shelter, water and minerals to the alga and in return, the alga „ provides.

Question 10.
What is parasitism? Give examples.
Answer:

1. Type of association between two organisms for food in which one organism get benefited and other is vitiated is called parasitism (Parasitic nutrition).
2. The organism which is getting benefit is called parasite.
3. Example for parasitic plant is Cuscuta.
4. Example for parasitic animal is intestinal worm.

Question 11.
How does dodder plant get its food?
Answer:

1. Plants like Cuscuta/ Dodder plant (Bangaru teega) take readymade food from the plant on which it is climbing. ,
2. They develop special roots called haustoria, which penetrate into the tissues of the host plant and absorb food materials from them.
3. This causes harm to the host plant gradually.
4. This kind of nutrition is called parasitism.

Question 12.
How do animals take their food? Where do they digest it?
Answer:

1. Animals obtain their food from other organisms.
2. They take their food in the form of solid or liquid.
3. They take the food into the body for digestion.
4. Digestion occurs inside the body.

Question 13.
What are the parts of human digestive system?
Answer:

1. The digestive system consists of the alimentary canal and digestive glands.
2. The total length of alimentary canal is about 9 meters.
3. Its main parts are mouth, oral cavity/ buccal cavity, oesophagus, stomach, small intestine, large intestine, rectum and anus.
4. The salivary glands, liver and pancreas are the digestive parts connected to the alimentary canal.

Question 14.
Write a short note on tooth decay?
Answer:

1. Normally Bacteria present in our mouth are not harmful to us.
2. If we do not clean our teeth and mouth after eating, many harmful bacteria begin to live and grow in it.
3. These bacteria breakdown the sugars present from leftover food and release acids.
4. These acids gradually damage teeth. This is called tooth decay.
5. If it is not treated in time, it causes severe toothache and in extreme cases results in tooth loss.
6. Chocolates, sweets, soft drinks and other sugar products are major causes of tooth decay.

Question 15.
How do bad habits effect our digestive system?
Answer:

1. Bad habits like smoking, chewing of tobacco, drinking of alcohol effect our health adversely. .
2. Drinking of alcohol can lead to liver diseases, digestive problems.
3. It causes cancer of the mouth, throat, oesophagus arid liver.
4. Consuming tobacco products, tobacco particles stick to teeth, gums, and skin of the mouth cavity which leads to swelling, injury, pain and also causes throat and intestine cancer.

Question 16.
How do vajrasana help our body?
Answer:

1. Vajrasana increases flow of blood into our stomach area, thus improving our bowel movements and relieving constipation.
2. It also keeps us to get rid of gas and acidity.

Question 17.
Draw the diagram of stomata and label the parts.
Answer:

Question 18.
Draw the diagram showing nutrition in amoeba.
Answer:

Question 19.
Which habit should be practised for the health of teeth? Why?
Answer:
We should clean our teeth daily at least for twice. Once in the morning after we wakeup. This helps to remove the bacteria accumulated over night in our mouth. And second time before going to bed. This helps to remove any food particles remain in mouth. Otherwise these food particles increase the growth of bacteria and releasing of acids. So for the health of our teeth, we should brush our teeth at least for twice.

7th Class Science 3rd Lesson Nutrition in Organisms Long Questions and Answers

Question 1.
What is nutrition? Describe different types of nutritions.
Answer:
The process of intake and utilization of food by organisms is called nutrition. This is mainly of two types.

1. Autotrophic nutrition
2. Heterotrophic nutrition

1) Autotrophic nutrition :
The mode of nutrition in which organisms make food by themselves is called autotrophic nutrition. Ex: Green plants

2) Heterotrophic nutrition :
The mode of nutrition in which organisms depend on other organisms for food is called Heterotrophic nutrition. This is again of three types
i) Saprophytic nutrition:
The mode of nutrition in which organisms take in nutrients in the form of solution from dead and decaying matter is called saprophyticnutrition.
Ex: Certain microorganisms such as bacteria and fungi like mushrooms, bread mould etc.

ii) Parasitic Nutrition :
This type of association between two organisms for food in which one organism get benefited and other is vitiated is called parasitic nutrition.
Ex: Cuscuta, Intestinal worms

iii) Holozoic Nutrition :
Holozoic Nutrition is the mode of heterotrophic nutrition in which the food is taken in solid or liquid form from the outside and is digested inside the body.
Ex: Amoeba. Human beings

Question 2.
What is holozoic nutrition? What are the steps involved in it?
Answer:
Holozoic Nutrition is the mode of heterotrophic nutrition in which the food is taken in solid or liquid form from the outside and is digested inside the body.

The steps involved in holozoic nutrition are

1. Ingestion – Food is taken into the body.
2. Digestion – Conversion of food into simple soluble forms.
3. Absorption – Transfer of food to the blood.
4. Assimilation – Absorbed food became the part of the body. .
5. Egestion – Removal of waste products and undigested food from the body.

Question 3.
Describe the nutrition in amoeba.
Answer:

1. Amoeba is a microscopic single-celled organism found in pond water.
2. Amoeba has a cell membrane, a rounded, dense nucleus and many small bubble¬like vacuoles in its cytoplasm.
3. Amoeba constantly changes its shape and position.
4. It pushes out one. or more finger-like projections, called pseudopodia or false feet ‘ for movement and capture of food.
5. Food vacuole forms around the captured food.
6. Food get digested in it, absorbed into the cytoplasm and assimilates.
7. Finally undigested food is sent out by opening this vacuole out at the body surface.

Question 4.
Is the nutrition in human beings holozoic? Justify your answer.
Answer:

1. Yes, nutrition in human beings is holozoic nutrition.
2. We take food in the form of solids or liquids.
3. It get’s digested in the digestive system.
4. Digested food is absorbed by the blood.
5. Blood transports digested food to different parts of the body for assimilation.
6. Undigested food will be ejected out of the body.
7. So the nutrition in human beings is holozoic nutrition.

Question 5.
Explain the process of digestion in grass eating animals.
Answer:

1. Grass eating animals have four chambers in stomach.
2. They are rumen, reticulum, omasum and abomasum.
3. They quickly swallow the grass and store it in a part of the stomach called rumen.
4. In rumen, food gets partially digested and is called cud.
5. But later the cud returns to the mouth in small lumps and animal chews it again.
6. This process is called rumination and these animals are called ruminants.
7. The grass is rich in cellulose, a type of carbohydrate.
8. In ruminants, the cellulose of the food is digested by the action of certain bacteria present in the rumen of grass eating animals.

Question 6.
Make a table showing types of teeth, their number and function in human beings.
Answer:

Question 7.
Describe the functions of various parts of human digestive system.
Answer:
Different parts of human digestive system performs different functions as mentioned below.

1. Mouth Food is taken into the body through it. It leads into Buccal Cavity.
2. Buccal cavity contains tongue, teeth and secretions of Salivary glands. Carbohydrate digestion starts here.
3. Pharynx is the common chamber for both digestive track and respiratory track. It leads into Oesophagus.
4. Oesophagus is a muscular tubular structure that connects pharynx with Stomach.
5. Stomach is a muscular sac like structure. Food is grinded well and mix with its juices. Proteins digestions tarts in the stomach. Hydrochloric acid in the stomach kills Bacteria in the food.
6. Duodenum is the first part of the small intestine. Bile juice from liver, Pancreatic juice from pancreas enters into it and helps in digestion.
7. Small intestine is about six metre long. Digestion of food is completed here with the help of its juices. Its inner wall have thousands of finger-like outgrowths called villi. They absorb the digested food. Blood transport it to all body parts for assimilation.
8. Large Intestine absorbs water and minerals from the undigested food.
9. Rectum storage point for undigested food.
10. Anus – Fecal matter removed through it.

Question 8.
What is acidity? Mention the symptoms, causes and home remedies for acidity.
Answer:
Acidity:
It’s a common problem associated with digestive track caused due to excess acids in stomach.

Symptoms :
Burning sensation in chest, stomach and in throat;
sour taste in mouth;
upper abdominal discomfort;
post meal heaviness.

Causes : consuming spicy food;
stress;
unhealthy or irregular meals;
drinking too much alcohol.

Home remedies:
Consuming butter milk, coconut water, eating of herbs such as ajwain, tulsi leaves, saunf, jeera and pudina leaves, cloves, jaggery

AP Board 7th Class Science 3rd Lesson 1 Mark Bits Questions and Answers Nutrition in Organisms

I. Multiple Choice Questions

1. Carbohydrates digest first in
A) Buccal cavity
B) Stomach
C) Small intestine
D) Large intestine
Answer:
A) Buccal cavity

2. Proteins digestion starts in
A) Buccal cavity
B) Stomach
C) Small intestine
D) Large intestine
Answer:
B) Stomach

3. Chocolates, sweets, soft drinks and other sugar products cause of
A) Acidity
B) Constipation
C) Tooth decay
D) Diarrhea
Answer:
C) Tooth decay

4. The process of intake and utilization of food by organisms is called ……
A) Digestion
B) Absorption
C) Nutrition
D) Excretion
Answer:
C) Nutrition

5. Nutrition in green plants is
A) Autotrophic
B) Saprophytic
C) Parasitic
D) Holozoic
Answer:
A) Autotrophic

6. This is not a requirement of photosynthesis
A) Oxygen
B) Carbon dioxide
C) light
D) water
Answer:
A) Oxygen

7. Product of photosynthesis
A) Oxygen
B) Water
C) Glucose
D) All the above
Answer:
D) All the above

8. Presence of starch in leaves indicates the occurrence of…..
A) Respiration
B) Photosynthesis
C) Digestion
D) Excreton
Answer:
B) Photosynthesis

9. This works as food factory of the plant
A) Stem
B) Leaf
C)Flower
D) Root
Answer:
B) Leaf

10. Function of stomata is
A) Gaseous exchange
B) Transport of water
C) Food production
D) Digestion
Answer:
A) Gaseous exchange

11. Find the correct statement
i) Nepenthes is a insectivorous plant.
ii) It grow in phosphorous deficient soils.
A) both are correct
B) i only correct
C) ii only correct
D) both are wrong
Answer:
B) i only correct

12. Example for saprophyte
A) Amoeba
B) Utricularia
C) Cuscuta
D) Bread mould
Answer:
D) Bread mould

13. Chlorophyll-containing partner in the lichens is
A) Algae
B) Fungi
C) Bacteria
D) Amoeba
Answer:
A) Algae

14. Cuscuta absorbs its food from host through
A) Tap root
B) Fibrous root
C) Haustoria
D) prop roots
Answer:
C) Haustoria

15. National Deworming Day is observed on
A) February 10
B) August 10
C) Both A & B
D) December 10
Answer:
C) Both A & B

16. Albendazole tablet is a…
A) Antibiotic
B) Antiviral drug
C) Antifungal drug
D) Deworming drug
Answer:
D) Deworming drug

17. Taking of food into the body is called…..
A) Ingestion
B) Digestion
C) Absorption
D) Egestion
Answer:
A) Ingestion

18. Conversion of food into simple soluble forms is called …
A) Ingestion
B) Digestion
C) Absorption
D) Egestion
Answer:
B) Digestion

19. Transfer of food to the blood is called …..
A) Ingestion
B) Digestion
C) Absorption
D) Egestion
Answer:
C) Absorption

20. Removal of waste products and undigested food from the body
A) Ingestion
B) Digestion
C) Absorption
D) Egestion
Answer:
D) Egestion

21. Amoeba collects its food with the help of
A) Pseudopodia
B) Nucleolus
C) Food vacuole
D) Cytoplasm
Answer:
A) Pseudopodia

22. This is not digestible in human being is …..
A) Starch
B) Protein
C) Fat
D) Cellulose
Answer:
D) Cellulose

23. Nutrition in human being is …
A) Autotrophic
B) Parasitic
C) Saprophytic
D) Holozoic
Answer:
D) Holozoic

24. The total length of alimentary canal is about
A) 3 meters
B) 6 meters
C) 9 meters
D) 12 meters
Answer:
C) 9 meters

25. Tofal number of teeth in the adult is
A) 8
B) 16
C) 20
D) 32
Answer:
D) 32

26. Teeth that help to cut the food….
A) incisors
B) canines
C) premolars
D) molars
Answer:
A) incisors

27. Hardest part of the human body is
A) Bone
B) Teeth
C) Cartilage
D) Muscle
Answer:
B) Teeth

28. The major culprits of tooth decay ….
A) Chocolates
B) Sweets
C) Soft drinks
D) All the above
Answer:
D) All the above

29. Common chamber for both digestive track and respiratory track is
A) Pharynx
B) Duodenum
C) Esophagus
D) Buccal cavity
Answer:
A) Pharynx

30. The muscular tubular structure that connects pharynx with Stomach is
A) Buccal cavity
B) Oesophagus
C) Duodenum
D) Small intestine
Answer:
B) Oesophagus

31. Hydrochloricacid in the stomach kills Bacteria in the food.
A) Lactic acid
B) Sulphuric acid
C) Acetic acid
D) Hydrochloric acid
Answer:
D) Hydrochloric acid

32. Digestion of food completes in this part
A) Stomach
B) Duodenum
C) Small intestine
D) Large intestine
Answer:
C) Small intestine

33. Digested food absorbed in to blood through
A) Stomach
B) Duodenum
C) Villi
D) Large intestine
Answer:
C) Villi

34. Large intestine absorbs….
A) Water
B) Digested food
C) Minerals
D) A & C
Answer:
D) A & C

35. Reason for acidity…
A) Stress
B) Irregular meals
C) Drinking too much alcohol
D) All the above
Answer:
D) All the above

36. The only asana that can be done on full stomach.
A) Padmaasan
B) Vajrasana
C) Bhujangasana
D) shirshaasana
Answer:
B) Vajrasana

II. Fill in the blanks

1. Liver produces …………… juice.
2. Expand NDD ……………
3.
4. The process of intake and utilization of food by organisms is called …………… .
5. The mqde of nutrition in which organisms make food by themselves is called …………… .
6. The mode of nutrition in which organisms depend on other organisms, for food is called …………… .
7. Green plants are …………… .
8. Humans and animals are directly or indirectly dependent on …………… for food.
9. …………… are the special structures present only in plant cells and absent in animal cells.
10. Chlorophyll is present in the …………… of plant cell.
11. …………… is the pigment responsible for the greenery of the plants.
12. The process-by which green plants make their own food from carbon dioxide and water by using light energy in the presence of chlorophyll is called …………… .
13. Glucose formed in photosynthesis is converted and stored in the form of …………… .
14. The presence of starch in leaves indicates the occurrence of …………… .
15. Occurrence of photosynthesis can be confirmed by testing the leaf extract with …………… solution.
16. …………… work as “food factories of plants”.
17. …………… captures the energy of the sunlight.
18. …………… is the source of energy in the process of photosynthesis.
19. …………… is the ultimate source of energy for all living organisms.
20. Gaseous exchange occurs in the leaves through …………… .
21. …………… is the gas required for photosynthesis.
22. …………… is the gas produced in photosynthesis.
23. Nutrients needed ip minute quantities are called …………… .
24. Insectivorous plants meet their requirements from insects.
25. Saprophytes grow on …………… .
26. The mode of nutrition in which organisms take in nutrients in the form of solution from dead and decaying matter is called …………… nutrition.
27. …………… play key role in cleaning,up the earth surface.
28. Chlorophyll-containing partner in lichen is
29. An association between two organisms for food in which one organism get benefited and other is vitiated is called ……………
30. The organism that get benefited in parasitism is …………… .
31. Organism on which parasite is growing is called …………… .
32. …………… is the mode of heterotrophic nutrition in which the food is taken in solid or liquid form from the outside and is digested inside the body.
33. Pseudopodia are food collecting, organs in …………… .
34. Humans cannot digest …………… .
35. The digestive system consists Of the …………… and …………… .
36. The total length Of alimentary canal is about …………… meters.
37. Teeth in the human beings are of …………… types.
38. …………… is the hardest part of the human body.
39. …………… is the only asana that can be done on full stomach.
40. Damage of teeth due to acids is called …………… .
41. Carbohydrate digestion starts in …………… .
42. …………… is the common chamber for both digestive track and respiratory track.
43. Proteins digestions starts in the …………… .
44. …………… in the stomach kills Bacteria in the food.
45. Inner wall of the small intestine have thousands of finger-like outgrowths called …………… .
46. Villi absorb the …………… .
47 …………… absorbs water and minerals from the undigested food.
48. …………… is the storage;point for undigested food.
49. Fecal matter removed through …………… .
Answer:

1. bile
2. National Deworming Day
3. carbondioxide, oxygen
4. nutrition
5. autotrophic nutrition
6. heterotrophic nutrition
7. autotrophs
8. plants
9. Chloroplasts
10. chloroplast
11. Chlorophyll
12. Photosynthesis
13. starch.
14. photosynthesis
15. Iodine
16. Leaves
17. Chlorophyll
18. Sunlight
19. Sun
20. stomata.
21. Carbon dioxide
22. Oxygen
23. micronutrients
24. nitrogen
25. dead and decaying matter
26. saprophytic
27. Saprophytes
28. algae
29. parasitism.
30. parasite
31. host
32. Holozofc Nutrition
33. amoeba
34. cellulose
35. Tooth
36. Vajrasana
37. tooth decay
38. buccal cavity
39. Pharynx
40. stomach
41. Hydrochloric acid
42. villi.
43. digested food
44. Large Intestine
45. Rectum
46. anus.

III. Match the following

1.

Answer:

2.

Answer:

3.

Answer:

4.

Answer:

Do You Know?

→ Forests are green in colour. Isn’t it? Infact they are green as they have many trees. Trees are green as they have leaves. Leaves are green as they have chloroplasts. Chloroplasts are the special structures present only in plant cells and absent in animal cells.These chloroplasts consists of a green coloured pigment called chlorophyll in them,. This chlorophyll is responsible for all this greenery and play key role in preparation of food. You will learn about all these in your higher classes.

→ There are some plants that eat insects. Being green in colour, they can manufacture their own food. But as they grow in areas deficient in Nitrogen, they meet their Nitrogen requirements from insects. Leaves of these plants are specially modified to trap insects. Nepenthes, (pitcher plant) Droseras, Utricularia (bladderwort), Dionaea (Venus fly trap) are examples of some such insectivorous plants. These are also called as carnivorous plants.

→ Some plants of the Dal family (legume plants) possess a type of bacteria growing on their roots in nodules. The bacteria fixes nitrogen for the plant while it gets shelter in the roots of these plants. Such an association is beneficial to both groups and is called Symbiosis.

In organisms called lichens (litmus paper is obtained from lichens), a chlorophyll-
containing partner, which is an algae and a fungus live together. The fungus provides shelter, water and minerals to the algae and in return, the algae provides food for the fungus.

→ Every year February 10 and August 10 is observed as the National Deworming Day(NDD). The day aims at eradicating intestinal worms among children in the age group of 1-19 years. On this day. Albendazole tablet (deworming drug) is administered to children.

Digestion In Grass Eating Animals

→ Have you observed cows, buffaloes and other grass eating animals chewing continuously even when they are not eating? They have four chambers in stomach. They are rumen, reticulum,omasum and abomasum. Actually they quickly swallow the grass and store it in a, part of the stomach called rumen. In rumen, food gets partially digested and is called cud. But later the cud returns to the mouth in small lumps and animal chews it again. This process is called rumination and these animals are called ruminants.

The, grass is rich in cellulose, a type of carbohydrate. In ruminants, the cellulose of the food is digested by the action of certain bacteria present in the rumen of grass eating animals.Many animals including humans cannot digest cellulose due to the absence of such bacteria.

→ Normally Bacteria present in our mouth are not harmful to us. If we do not clean our teeth and mouth after eating, many harmful bacteria begin to live and grow in it. These bacteria breakdown the sugars present from leftover food and release acids. These acids gradually damage teeth. This is called tooth decay. If it is not treated in time, it causes severe toothache and in extreme cases results in tooth loss. Chocolates, sweets, soft drinks and other sugar products are the major causes of tooth decay

→ Vajrasana increases flow of blood into our stomach area, thus improving our bowel movements and relieving constipation. It also keeps us to get rid of gas and acidity. It is the only asana that can be done on full stomach.