Question

Match the columns and choose the correct answer.

	I		II
p	Thiobacillus denitrificans	i	Nitrogen fixation
q	Nitrosomonas	ii	Ammonification
r	Azotobacter	iii	Nitrification
s	Bacillus vulgaris	iv	Denitrification

• A. p - iv, q - iii, r - i, s - ii
• B. p - iii, q - iv, r - i, s - ii
• C. p - iv, q - ii, r- i, s - iii
• D. p - ii, q - i, r - iii, s - iv

Answer 1

The correct option is A p - iv, q - iii, r - i, s - ii

Denitrification is the process in which nitrates present in the soil are reduced to nitrogen. The bacteria that help in this process are Thiobacillus denitrificans and Pseudomonas denitrificans.
Nitrification is the process of oxidation of ammonia into nitrite by bacteria such as Nitrosomonas and later the nitrite is oxidised to nitrate by bacteria such as Nitrobacter.
Nitrogen fixation is the conversion of atmospheric nitrogen into compounds of nitrogen like nitrates and ammonia.
The organic nitrogen of dead plants and animals (decaying biomass) undergoes decomposition to release ammonia. This process is called ammonification. It is carried out by bacteria such as Bacillus vulgaris.