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Biological Classification

Short Answer Type

Discuss how classification systems have undergone several changes over a period of time?

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2.
State two economically important uses of:
(a) Heterotrophic bacteria
(b) Archaebacteria

The economic uses of the following are:
(a) Heterotrophic bacteria:
(i) Used as bio-fertilizers as they act as decomposers and help in the formation of humus and some of them fix nitrogen.
(ii) They help in the production of curd, various antibiotics etc. Many antibiotics are obtained from some species of bacteria

(b) Archaebacteria:
(i) Used for the production of biogas as they produce methane gas by acting on the excreta of animals.
(ii) They are used for the production of commercial products like heat stable enzymes.

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