Question 2
State two economically important uses of: (a) Heterotrophic bacteria (b) Archaebacteria
(a) Heterotrophic bacteria
(1) Many bacteria like Lactobacillus helps in the production of curd from milk.
(2) They act as decomposers and help in the formation of humus e.g. Pseudomonas.
(3) Many antibiotics are obtained from some species of bacteria like streptomyces, Bacillus etc.
(4) Many soil bacteria help in fixation of atmospheric nitrogen like Rhizobium (Symbiotic), Azotobacter (Free living).
(b) Archaebacteria
(1) Methane gas is produced from the dung of ruminants by the methanogens.
(2) Methanogens are also involved in the formation of biogas and sewage treatment.
