Andhra Pradesh BIEAP AP Inter 1st Year Botany Study Material 2nd Lesson Biological Classification Textbook Questions and Answers.

AP Inter 1st Year Botany Study Material 2nd Lesson Biological Classification

Very Short Answer Questions

Question 1.
What is the nature of cell-walls in diatoms?
Answer:
In Diatoms, the cell wall is made up of silica and thus the walls are Indestructible.

Question 2.
How are Viroids different from viruses? [Mar. 14]
Answer:

Viroids Viruses
1. Infectious agents which contains only nucleic acid [RNA] and without the protein coat.
Ex : Potato spindle tuber disease.		 1 Infectious agents which contains both Nucleic acid [RNA] and protein coat.
Ex : TMV

Question 3.
What do the terms phycobiont and mycobiont signify? [A.P. Mar, 17, Mar. 13]
Answer:
The Algal component in a lichen is called phycobiont. The fungal component in a lichen is called Mycobiont.

Question 4.
What do the terms ‘algal bloom’ and ‘Red Tides’ signify?
Answer:
In cyanobacteria :
The colonies and trichomes or filaments are surrounded by gelatinous sheath which often forms blooms in polluted water bodies called algal blooms.
Ex : Nostoc, Anabaena.

Red Dinoflagellates like “Gonyaulax” undergo rapid multiplication and make the sea “Red” so called Red Tides.

Question 5.
State two economically important uses of heterotrophic bacteria.
Answer:
Heterotrophic Bacteria help in making curd from milk, production of Antibiotics and Nitrogen fixation in legume roots.

AP Inter 1st Year Botany Study Material Chapter 2 Biological Classification

Question 6.
What is the principle underlying the use of cyanobacteria in agricultural fields for crop improvement? [A.P. Mar. 15]
Answer:
Cyanobacteria are used in Agricultural fields for crop improvement because they help in Nitrogen fixation and make the soil fertile and also they show oxygenic photosynthesis.

Question 7.
Plants are autotrophic. Name some plants which are partially heterotrophic.
Answer:
Partial heterotrophic plants are viscum, loranthus, striga.

Question 8.
Who proposed five Kingdom classification? How many Kingdoms of this classification contain eukaryotes?
Answer:
R.H.Whittaker proposed five kingdom classification. In this classification, four kingdoms [Protista, Fungi, Plantae, Animalia are Eukaryotes.

Question 9.
Give the main criteria used for classification by Whittaker. [T.S. May. 18, Mar, 15]
Answer:
The main cricteria for five kingdom classification include cell structure, thallus organization. Mode of Nutrition, reproduction and phylogenetic relationships.

Question 10.
Name two diseases caused by Mycoplasmas. [A.P. May. 18]
Answer:
Mycoplasmas cause witches broom disease in plants, pleuropneumonia in cattle and v mycoplasmal urethritis in Humans.

Question 11.
What are slime moulds? Explain what is meant by plasmodium with reference to slime moulds.
Answer:
Slime moulds are saprophytic protists. The multinucleated mass of protoplasm is surrounded by a plasamamembrane under favourable conditions, they form an aggregation called plasmodium.

Short Answer Type Questions

Question 1.
What are the characteristic features of Euglenoids?
Answer:

  1. Most of the euglenoids are Fresh Water organisms found in stagnant water.
  2. They have a protein rich layer called pellicle which makes body flexible.
  3. They have Two flagella, a short and a long one.
  4. The anterior part of the cell bears an invagination consisting of cytostome, cytopharynx and reservoir.
  5. Eye spot or photosensitive stigma is present in the reservoir.
  6. They behave as heterotrophs when deprived of sunlight.
  7. The reproduction is by lohgitudinal binary fission.

AP Inter 1st Year Botany Study Material Chapter 2 Biological Classification

Question 2.
What are the advantages and disadvantages of Two kingdom classification?
Answer:
Advantages :

  1. The two kingdom classification received considerable recognition from biologists and was in use for quite a long period of time.
  2. Classification of organisms into plants, animals was easily done and was easy to understand.
  3. The character that unified this whole kingdom was that all organisms included had a cell wall in their cells.

Disavantages :
1. There is no clear Cut distinction in the lower forms of life into plants and animals. Euglena for example is a unicellular organism having certain features of criminals and certain features of plants. If has a flagellum which is used for locomotion and food capturing. However it has chloroplasts like plant cells.

2. Chlomyclomonas is a unicellular algue. It is purely antotrophic but has 4 locomotor structures called flagella like protozoans.

3. The classification did not differentiate between the heterotrophic group, fungi and the autotrophic green plants through they also showed a characteristic difference in their wall composition. Hence two kingdom classification used for a lone time was found inadequate.

Question 3.
Give the salient features and importance of chrysophytes. [A.P. Mar, 15, 13]
Answer:
Chrysophytes includes diatoms and golden algae (desmids). They are found in freshwater as well as in marine water.’Most of them are photosynthetic. In diatoms the cell wall form two thin overlapping shells, epitheca over hypotheca which fit together as soap box. The walls are embedded with silica and thus the walls are indestructible. Diatoms leave larger amount of cell wall deposits in their habitat, this accumulation is referred as diatomaceous earth or kieselghur. They reproduce a sexually by Binary fission and sexually by gametes.

Importance :

  1. The diatomaceous soil is used in polishing, filtration of oils 8 syrups.
  2. Diatoms are the chief “producers” in the oceans.

Question 4.
Give a brief account of Dinoflagellates. [A.P. May, 18, Mar, 18] [T.S. Mar, 15]
Answer:

  1. Dinoflagellates are mostly marine and photosynthetic.
  2. The cell wall has stiff cellulose plates on the outer surface.
  3. They have two flagella and produce spinning movements. So these protists are called “whirling whips”.
  4. The nucleus has condensed chromosomes, which are without histones.
  5. Some Dinoflagellates like Noctiluca show bioluminescence.
  6. Red dinoflagellates like Gonyaulax undergo rapid multiplication and make the sea appear red
    (Redtides in Medeterranelian sea)
  7. Toxins produced by them may kill fishes.

AP Inter 1st Year Botany Study Material Chapter 2 Biological Classification

Question 5.
Write the role of Fungi in our daily life. [T.S. May, 18. Mar, 14]
Answer:
The role of Fungi in our dialy life show some uses and disuses. They are :
Uses :

  1. Yeast are used to make bread and beer.
  2. Some Fungi like penicillium are the source of antibiotics. (Penicilin)
  3. Some Fungi like Agaricus are edible mushrooms.

Disuses :

  1. Some Fungi cause rot of orange fruits
  2. Spoilage of bread
  3. White spots are seen in musterd leaves by Albugo.
  4. Some Fungi (Puccinia) cause rust in wheat.

Long Answer Type Questions

Question 1.
Give the salient features and comparative account of different classes of fungi studied by you.
Answer:
A) Phycomycetes :

  1. They are found in Aquatic habitats and on decaying wood or as obligate parasites on plants. They arealso called algal fungi.
  2. The mycelium is aseptate and coenocytic.
  3. A sexual reproduction takes place by zoospores or by aplanospores.
  4. Zygospores are formed by the fusion of two gametes which may similar (Isogamous) or dissimilar (Anisogamous) or oogamous.
    Ex : Mucor, Rhizopus, Albugo.

B) Ascomycetes :

  1. They are commonly called “sac fungi”
  2. They are unicelluar (yeast) or multicellular (Penicillium).
  3. They are saprophytic, decomposers, parasitic or coprophilous (growing on dung).
  4. The mycelium is Branched and septate.
  5. The reproduce asexually by conidia, produced on conidiophores.
  6. Sexual spores are called ascospores Ex : Aspergillus, pencillium, ckiviceps.

C) Basidiomycetes :

  1. They are commonly known as Mushrooms, bracket fungi or puffballs or club fungi.
  2. They grow in soil, on logs and tree stumps and in living plant bodies as parasites.
    Ex : Rusts.
  3. The mycelium is branched and septate.
  4. The asexual spores are not found but common method is fragmentation.
  5. Sex organs are absent.
  6. Plasmogamy takes place by the fusion of two vegetative cells of different strains or genotypes.
  7. Karyogamy and Meiosis take place in the basidium producing basidiospores.
    Ex : Agaricus, ustilago, polyporus Lycoperdon.

D) Deuteromycetes :

  1. They are commonly known as imperfect fungi.
  2. Some members are saprophytes or parasites, while a large members are decomposers.
  3. The mycelium is branched and septate.
  4. They reproduce asexually and vegetatively.
  5. When the sexual stages were discovered, they were moved into another classes, asco or basidiomycetes.
    Ex : Alternaria, Colletotrichum, Trichoderma.

AP Inter 1st Year Botany Study Material Chapter 2 Biological Classification

Question 3.
Describe briefly different groups of Monerans you have studied.
Answer:
They indued Alio prokaryotes like Archaebacteria, Eubacteria, Mycoplasma and Actinomycetes.

I. Archaebacteria :

  1. They live in salty areas, hot springs or in Marshy places.
  2. The cell wall contains pseudomurein.
  3. The cell membrane contains branched chain lipids.
  4. Methanogens are present in the gut of ruminant animals, and are responsible for the production of methane gas from the dung.

II. Eubacteria :

  1. They occur almost everywhere, such as hotsprings, deserts, snow and deep oceans as parasites and as symbionts.
  2. They are classified-into spherical coccus, rod shaped bacillus, the comma shaped vibrio and the spiral shaped spirillum, based on their shape.
  3. The cell wall is made up of peptidoglycan.
  4. The cell membrane shows infoldings called mesosomes.
  5. They contain 70s type of ribosomes along with naked genetic material (nucleoid).
  6. Some of eubacteria are autotrophic and the vast majority are heterotrophs.
  7. Cyanobacteria like Nostoc and Anabaena are Unicellular, colonial or filamentous, aquatic or terrestrial algae.
  8. They often forms blooms in polluted water bodies. Some of them can fix Atmospheric Nitrogen in specialised cells called Heterocysts.

III. Mycoplasma :

  1. They completely lack a cell wall and are pleomorphic.
  2. They are smallest living cells and can survive without oxygen.
  3. They cause diseases in plants [witches broom]; in cattle (pleuropneumonia) and in humans (Mycoplasmal urethritis).

IV. Actinomycetes :

  1. They are branched, filamentous bacteria.
  2. The cell wall contains mycolic acid.
  3. Most of them are saprophytic and decomposers.
  4. Some are (Mycobacterium and corynebacterium) parasites.
  5. A number of antibiotics are produced from the genus streptomyces.

AP Inter 1st Year Botany Study Material Chapter 2 Biological Classification

Question 3.
Enumerate the salient features of different groups in protista.
Answer:
I. Chrysophytes :

  1. Chrysophytes includes diatoms and golden algae (desmids).
  2. They are found in freshwater as well as in marine water.
  3. Most of them are photosynthetic.
  4. In diatoms the cell walls form two thin overlapping shells, epitheca over hypotheca which fit together as soap box.
  5. The walls are embedded with silica and thus the walls are indestructible.
  6. Diatoms leave larger amount of cell wall deposits in their habitat, this accumulation is referred as diatomaceous earth or kieselghur.
  7. They reproduce asexually by Binary fission and sexually by gametes. ‘

II. Dinoflagellates :

  1. Dinoflagellates are mostly marine and photosynthetic.
  2. The cell was has stiff cellulose plates on the outer surface.
  3. They have two flagella and produce spinning movements. So these protists are called “whirling whips”.
  4. The nucleus has condensed chromosomes, which are without histones.
  5. Some Dinoflagellates like Noctiluca show bioluminescence.
  6. Red dinoflagellates like Gonyaulax undergo rapid multiplication and make the sea appear red (Redtides in Medterranian sea)
  7. Toxins produced by them may kill fishes.

III. Euglenoids :

  1. Most of the euglenoids are Fresh Water organisms found in stagment water.
  2. They have a protein rich layer called pellicle which makes body flexible.
  3. They have Two flagella, a short and a long one.
  4. The anterior part of the cell bears an invagination, consisting of cytostome, cytopharynx and reservoir.
  5. Eye spot or photosensitive stigma is present in the reservoir.
  6. They behave as heterotrophs when deprived of sunlight.
  7. The reproduction is by longitudinal binary fission.

IV. Slime moulds :

  1. They are saprophytic protists. The multinucleated mass of protoplasm is surrounded by a plasamamembrane.
  2. Under suitable conditions, they form an aggregation called plasmodium.
  3. During unfavourable conditions, the plasmodium differentiates and forms fruiting bodies bearing spores at their tips.
  4. The spores are extremely resistant and are dispersed by air.

V. Protozoans :

  1. They live as predators or parasites.
  2. They do not contain cell wall.
  3. The protoplason is surrounded by plasma membrane.
  4. Among them. Amoeboid protozoans live in fersh water, sea water or moist soil. They move and capture their prey by pseudopodia.
    Ex : Entamoeba.
  5. Flagellated protozoans are either free living or parasitic.
  6. They have flagella.
  7. The parasitic forms cause diaseases such as sleeping sickness.
    Ex : Trypanosoma.
  8. Ciliated Protozoans : They are aquatic and actively moving organisms by having cilia.
  9. They have a cavity that opens to outside of the cell surface.
    Ex: Paramoecium.

IV. Sporozoans :
They have an Infectious spore like stage in their life cycle.
Ex : Plasmodium (Malarial parasite) causes Malaria in humans.

Intext Questions

Question 1.
State two economically important uses of :
a) Heterotrophic bacteria b) Archaebacteria
Answer:
a) Heterotrophic bacteria :
They help in making curd from milk, production of Antibiotics and \ Nitrogen fixation in legume roots.

b) Archaebacteria :
1) Produce methane 2) Used by humans in biotechnoogy.

Question 2.
Give a comparative account of the classes of Kingdom Fungi on the basis of the following :
i) mode of nutrition
ii) mode of reproduction.
Answer:
i) mode of nutrition :
a) Phycomycetes : Obligate parasites.
b) Ascomycetes : Saprophytic, decomposers.
c) Basidiomycetes : Parasites.

d) Deuteromycetes :
Saprophytes, decomposers, ii) mode of reproduction :
a) Phycomycetes : Asexually by zoospores or aplanospores, sexually by gametes.
b) Ascomycetes : Asexually by conidia, sexually by ascospores.
c) Basidiomycetes : Asexually by fragmentation, sexually by fusion of two somatic cells.
d) Deuteromycetes : Asexually by conidia.

AP Inter 1st Year Botany Study Material Chapter 2 Biological Classification

Question 3.
Give a brief account of viruses with respect to their structure and nature of genetic material. Also name four common viral diseases.
Answer:
Viruses are made up of Nucleic acid and protein. The Nucleic acid could be either RNA or DNA. The protein part is called capsid which encloses the Nucleic acid. Tobacco Mosaic virus and Human Immuno Virus (HIV) contains RNA as genetic material. Bacteriophages, contain DNA as genetic material.

Common viral diseases are –

  1. Tobacco Mosaic virus.
  2. Potato spindle Tuber disease.
  3. Human Immuno virus.
  4. Scrapie disease of sheep.

Question 4.
Organise a discussion in your class on the topic – Are viruses living or non-living?
Answer:
Viruses are not truly ‘living’. They exist in crystal form outside the host. They are called obligate parasites.

Question 5.
Suppose you accidentally find an old preserved permanent slide without a label and in your effort to identify it, you place the slide under microscope and observe the following features :
a) unicellular body
b) well defined nucleus
c) biflagellate condition – one flagellum lying longitudinally and the other transversely.
What would you identify it as? Can you name the kingdom it belongs to?
Answer:
Protistian cell. They belongs to kingdom protista.

Question 6.
Polluted water bodies have usually high abundance of plants like Nostoc and Oscillatoria. Give reasons.
Answer:
Abundence of reserved food materials.
– Increase the level of dissolved O2 in their environment.
– N2 fixing capacity.

AP Inter 1st Year Botany Study Material Chapter 2 Biological Classification

Question 7.
Cyanobacteria and heterotrophic bacteria have been clubbed together in Eubacteria of Kingdom Monera as per the five kingdom classification, even though the two are vastly different from each other. Is this grouping of the two types of taxa in the same kingdom justified? If so why?
Answer:
Grouping of the two types of tax a in the same kingdom is justified because both organisms contain ‘nif’ genes and are involved in Nitrogen fixation.

Question 8.
What observable features in Trypanosoma would make you classify it under kingdom protista?
Answer:

  1. They are free living or parasitic.
  2. They have flagella.

Question 9.
At a stage of their life cycle, ascomycetous fungi produce the fruiting bodies like cleistothecium perithecium or apothecium. How are these three types of fruiting bodies differ from each ohter?
Answer:
The globose ascocarp without opening is called cleistothecium.
The flask shaped ascocarp with an apical opening is called perithecium.
The cup or saucer shaped ascocarp is called apothecium.