Which of the following element helps in maintaining the structure of ribosomes?

1. Magnesium	2. Zinc
3. Copper	4. Molybdenum

The product(s) of the reaction catalyzed by nitrogenase in root nodules of leguminous plants is/are.
1. Nitrate alone
2. Ammonia and oxygen
3. Ammonia and hydrogen
4. Ammonia alone

Which of the following is a non–symbiotic nitrogen fixing bacteria?
1.  Rhizobium
2.  Mycorrhiza
3.  Azotobacter
4.  Nitrosomonas

Nitrogen-fixing bacteria converts:
1. $N_2$ $\to$ $N{H}_3$
2. $N{H}_4^{+}$ $\to$ $Nitrates$
3. $N{O}_2$ $\to$ $N{O}_3$
4. $N{O}_3$ $\to$ $N_2$

Plants take zinc in the form of:

Identify the incorrectly matched pair:

The major role of minor elements inside living organisms is to act as:
1. Co-factors of enzymes
2. Building blocks of important amino acids
3. Constituent of hormones
4. Binder of cell structure

Cytochrome is:
1.  Metallo flavo protein
2.  Fe containing porphyrin pigment
3.  Glycoprotein
4.  Lipid

Roots of which plant contains a pink pigment that has an affinity for oxygen:
1.  Carrot
2.  Soyabean
3.  Mustard
4.  Radish

For each molecule of ammonia produced during biological nitrogen fixation, the number of ATP molecules required is:
1. 4
2. 8
3. 12
4. 16