Give the biological names of the following: A symbiotic nitrogen-fixing bacterium found in root nodules.

The prokaryotic microorganisms that are capable of transforming or fixing the nitrogen gas from the atmosphere into absorbable form of nitrogen compounds are called nitrogen fixing bacteria. Rhizobium is a symbiotic bacterium that lives in the root nodules of leguminous plants and fixes atmospheric nitrogen into organic compounds. They fix the atmospheric nitrogen and convert it into soluble nitrates, nitrites and ammonium compounds. Nitrogen fixation helps in increasing soil productivity and soil fertility.

Give the biological names of the following: The fungus is being developed as a bio-control agent.

Biological control is a method of controlling pests that relies on natural predation. Bacteria, fungi, viruses, their enzymes, etc., are used as biocontrol agents. An example of the fungus that is being developed as a biocontrol agent is Trichoderma . It is a free-living, soil fungi generally found in the root region of the plant. A commonly used species is Trichoderma viridae . It is an effective biocontrol agent for several plant pathogens. It eliminates pathogens by mechanisms such as antibiosis, parasitism, competition, etc.

Give the biological names of the following: The microbe used to produce Swiss cheese.

Microbes contribute to the final flavor, smell, texture, and color of cheese. Specific microbes impart the characteristics of particular cheese. The microbe used to produce Swiss cheese is Propionibacterium sharmanii. Through the process of consuming the lactic acid, the bacteria produces acetate, propionic acid, and carbon dioxide as a by product. Its characteristic feature is formation of large holes due to production of large amount of CO 2 .

Give the biological names of the following: The microbe used to control insect larvae growing on cotton.

Biological control is a method of controlling pests that relies on natural predation. The microbe used to control insect larva on the cotton plant is Bacillus thuringiensis . It is used in the form of sprays or sachets as dry spores. These bacteria produce a toxin that kills the insect larvae by damaging their gut regions. The gene that produces toxins can be introduced into the cotton plant by genetic engineering method for creating insect-resistance plants.

Give the biological names of the following: The mould from which penicillin is obtained.

Antibiotics are chemical substances, produced by some microbes that can kill or retard the growth of other disease-causing microorganisms. Penicillin is an antibiotic that is commonly used for the treatment of various bacterial diseases. Penicillin is the first antibiotic discovered by Alexander Fleming from a fungus, Penicillium notatum . It is commercially prepared by using Penicillium chrysogenum .