Ammonia is first oxidized to nitrite by the bacteria except

1. Nitrosomonas

2. Nitrococcus

3. Nitrobacter

4. All of these

Consider the following statements:
Regarding plant mineral nutrition -
I. The deficiency symptoms of nitrogen, potassium and magnesium are visible first in senescent leaves.
II. Manganese inhibits calcium translocation in shoot apex.
III. Lack or low level of N, K, S, Mo causes an inhibition of cell division.
Which of the above statements are true?
1. I and II only           2. I and III only
3. II and III only         4. I, II, and III

What type of reaction is shown in the given figure?


1. Deamination
2. Reductive amination
3. Transamination
4. Nitrogenation

In the given diagram of a typical set up for nutrient solution culture, the purpose of X is:

1. Addition of water 2. Addition of nutrients 3. Removal of wastes 4. Aeration

Electrical nitrogen fixation leads to

Which of the type of fixation leads to fixation of atmospheric nitrogen to ammonia?

Decomposition of organic nitrogen of dead plants and animals into ammonia is called

In nature, ……….. and ……….. provide enough energy to convert Nitrogen to nitrogen oxides (NO, NO₂, N₂O).

Nitrogen:
Find the incorrect one.
1. Plants compete with microbes for it.
2. It is a limiting nutrient for both natural and agricultural ecosystem
3. Nitrogen has triple covalent bonds
4. Nitrogen fixation is conversion of nitrogen into nitrate

Which of the following micronutrients does not form components of fertiliser?