12
MCQ (Single Correct Answer)
Members of phycomycetes are found in
(i) Aquatic habitats
(ii) On decaying wood
(iii) Moist and damp places
(iv) As obligate parasites on plants
Choose from the following options.
A
(i) and (iv)
B
(ii) and (iii)
C
All of these
D
None of these
13
What is the principle underlying the use of cyanobacteria in agricultural fields for crop improvement?
Explanation
Cyanobacteria are used in agricultural crop improvement because of their adicity to fix atmospheric nitrogen and make it available to the plants. This improves the yield of the crops and also reduces the cost of application of nitrogen fertilisers. e.g., Anabena and Nostoc.
14
Suppose you accidentally find an old preserved permanent slide without a label. In your effort to identify it, you place the slide under microscope and observe the following features
(a) Unicellular (b) Well defined nucleus (c) Biflagellate-one flagellum lying longitudinally and the other transversely
What would you identify it as? Can you name the kingdom it belongs to?
Explanation
All unicellular eukaryotic organisms form a link between plants, and animals. There organisms possess a well defined nucleus with membrane bound organelles and reproduce either sexually or asexually.
The it presence of two flagella one placed longitudanally and other transversely in a furrow between wall plates makes this organisms to be placed under Kingdom-Protista.
15
How is the five kingdom classification advantageous over the two kingdom classification?
Explanation
The five kingdom classification, that is proposed by RH Whittaker is based upon cell structure, body structure (unicellular, multicellular), nutrition (autotrophic, heterotrophic) reproduction and way of living either aquatic, terrestrial, or arial and phylogenetic relationship.
So, it is more useful as compared to two kingdom system of classification which does not distinguish between prokaryotes and eukaryotes and no other kingdom except plant and animal are identified.
16
Polluted water bodies have usually very high abundance of plants like Nostoc and Oscillitoria. Give reasons.
Explanation
Polluted water bodies possess high algal growth due to the presence of nutrient. These nutrients increase the rapid growth of water plants, i.e., algae especially Nostoc and Oscillitoria, etc., and result in colonies. These colonies are generally surrounded by a gelatinous sheath and furtherleads to the formation of blooms in water bodies.