Question

The different steps in a nodule formation are given below.
I. A mature nodule establishes a direct vascular connection with the host for exchange of nutrients.
II. Root hair curls and the bacteria invade the root hair.
III. Rhizobium bacteria contact a susceptile root hair, divide near it
IV. The infection thread is produced carrying the bacteria and grows into the cortex of the root.
V. The bacteria get modifi ed into rod-shaped bacteroids and cause inner cortical layer and pericycle to divide to form nodule.
The correct sequence is

• A. I, II, IV, V
• B. III, II, IV, V, I
• C. III, II, IV, I, V
• D. I, III, V, II, IV

Answer 1

Answer: (B)

Correct answer is (b) III, II, IV, V, I