Reduction of nitrogen to ammonia by living organisms is called as

(1) Electrical Nitrogen Fixation

(2) Biological Nitrogen Fixation

(3) Industrial Nitrogen Fixation

(4) Both B and C

Which of the following enzyme is exclusively in prokaryotes?

Nitrogenase converts

Which of the following is a symbiotic nitrogen fixer?

Which of the following is free living nitrogen fixing cyanobacteria?

Rhizobium

The most common association on roots is as

Rhizobium and Frankia

The central portion of nodule is pink in color due to

These are the events of Nodule formation:
a. Rhizobia get attached to epidermal and root hair.
b. Rhizobia multiply and colonise the surroundings of roots
c. Bacteria invade the root hair
d. The root hairs curl
e. An infection thread is produced
f. Bacteria are released from the thread into the cells
g. Infection thread carries the bacteria into the cortex of the root
h. The release of bacteria into cortex leads to the differentiation of specialised nitrogen fixing cells
i. Establishment of a direct vascular connection with the host for exchange
j. Nodule is formed finally
k. Initiation of nodule formation in the cortex of the root
Arrange them in order.
1. b-a-d-c-e-g-f-k-i-h-j
2. b-a-c-d-g-e-f-k-h-j-i
3. b-a-d-c-e-g-k-f-h-j-i
4. a-b-c-d-e-g-k-f-j-i-h