Match Column-I with Column- II.

	Column I		Column II
(a)	Nitrococcus	(i)	Denitrification
(b)	Rhizobium	(ii)	Conversion of ammonia to nitrite
(c)	Thiobacillus	(iii)	Conversion of nitrite to nitrate
(d)	Nitrobactèr	(iv)	Conversion of atmospheric nitrogen to ammonia

Choose the correct answer from the options given below.

	(a)	(b)	(c)	(d)
1.	(iii)	(i)	(iv)	(ii)
2.	(iv)	(iii)	(ii)	(i)
3.	(ii)	(iv)	(i)	(iii)
4.	(i)	(ii)	(iii)	(iv)

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

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

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

Plants take zinc in the form of:

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. $N{O}_3$ $\to$ $N_2$

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

All of the following statements concerning the Actinomycete filamentous soil bacterium Frankia are correct EXCEPT that Frankia
1. Forms specialized vesicles in which the nitrogenase is protected from oxygen by a chemical barrier involving triterpene hopanoids
2. Can induce root nodules on many plant species
3. Like Rhizobium, it usually infects its host plant through root hair deformation and stimulates cell proliferation in the host's cortex
4. Cannot fix nitrogen in the free-living state 

Study the cycle shown below and select the option which gives correct words for all the four blanks A, B, C and D :

Options :

Which of the following is a symbiotic nitrogen fixer?
1. Glomus
2. Azotobacter
3. Frankia
4. Azolla