Why do we prefer to call secondary wastewater treatment as biological treatment?

1

(a)

Secoundary wastewater treatment is called biological treatment as it uses microorganisms for treating the waste.

What would have happened if antibiotics were not discovered?

1

(a)

The mortality rate would have increased due to various bacterial diseases which are otherwise controlled by antibiotics.

Why is cow dung used in the generation of biogas?

1

(a)

Cow dung contains
(i) Celluosic materials and 
(ii) Methanoges, i.e, the raw material and the microbes needed for production of biogas.

What would happen if our intestine harbors microbial flora exactly similar to that found in the rumen of cattle?

1

(a)

Microbial flora present in the rumen of cattle takes part in digestion of cellulose. Presence of this microbial flora will enable us to digest cellulose.

Citric acid is available in the market and acts as an excellent food preservative, can you name the microorganism out of which it is extracted?

1

(a)

Aspergillus niger (A fungus)

A farmer was practicing mono culture in his field .Then he was advised to raise paddy crops in his field. He raised after that he observed a boom in the fertility of the field. What can be the reason behind it? Justify your answer.

1

(a)

Nitrogen fixation by autotrophic microbes cyanobacteria e.g. Anabaena, Nostoc, Oscillatoria. Cyanobacteria enrich the soil with organic matter and nitrogen components.

As Saccharomyces cerevisiae produces CO2 during fermentation, if fermented dough of Aspergillus niger is used to make bread, then what happens on its consumption?

1

(a)

Food will produce toxicity because Aspergillus niger produce aflatoxins.

Raman underwent kidney transplantation after which he observed allergic reactions. Can you suggest the name of microbial product and its source for controlling them.

1

(a)

Product : cyclosporine A, Source : Trichoderma polysporum (fungi)

Swati knows that the cow excreta contains a specific bacteria. Name the type of bacteria and how it can be socially used.

1

(a)

Methanogens (Archebacteria), Social use: lightening & cooking by using gobar gas.

GM crops are favored by some countries, while in India it is still banned. Can you suggest merits and demerits of such crops?

1

(a)

Merits : Enhance the quality & quantity of crops, less requirement of insecticide & pesticides, improve agronomic characteristics. Demerits : Favors new pathogen strain , dependability of farmers on biogenic companies.