Question

Microbiology help

The world around us is filled with bacteria, viruses, and fungi. For each of these types of organisms, post your ideas as to the good and also not so desirable qualities of each. Give some examples of specific properties, useful products which come from these, good things, and problems they can cause.  

Answer 1

Bacteria are the prokaryotes which act both as foe and friend for human. Some bacteria like Rhizobium in root nodules in legumes play an important role in nitrogen fixation and act as natural fertilizers. Bacteria and fungi decompose dead plants and animals so play role in nutrient recycling. Bacteria decompose harmful organic material of sewage into harmless soluble inorganic materials, during this process some methanogenic bacteria like Methanococcus releases methane(used as biogas).Lactobacillus lactis is the bacteria responsible for converting milk into curd. Acetobacter aceti is used to prepare acetic acid in industry. Bacteria are also utilized to prepare antibiotics i.e. streptomycin from streptomyces griseus,neomycin from S. fradiae. E.coli in intenstine of man helps to produce vitamins.

harmful activities of bacteria- These causes plant and animal disease like anthrax in cattle tuberculosis in man(by Myobacterium tuberculosis). They spoil food and cause food poisoning. Some bacteria like Thiobacillus denitrificans causes denitrification of soil and reduces soil fertility.

some fungi provide food(Agaricus sp.) while some are highly poisonous. yeast is used in baking industry and in fermentation of sugars into alcohol. Penicillium notatum provide very useful antibiotic penicillin. Negative aspect of fungi is that these causes a number of plant diseases like powdery mildew, rust, smut and blight etc. Fungi destructs timber. These spoil the food i.e. Rhizopus spoils bread.

Algae is utilized for food i.e. Porphyra Ulva etc. Chlorella is utilized for its high protein content. In industry red alga is used forprepration of agarmalgin and carrageenin. Nostoc and Anabaena fix nitrogen.Most harmful effect of algae is that these cause water blooms that emit bad smell in water bodies. Water blooms leads to death of fishes and other fauna in the water.