Question

Sequence the principal stages of biological nitrogen fixation in their correct order of occurrence.
(A) Formation of infection thread
(B) Rhizobium multiply to colonize.
(C) Curling of root hair.
(D) Differentiation of cortical cells into nitrogen fixing cells

• A. (B), (C), (A), (D)
• B. (A), (B), (C), (D)
• C. (B), (A), (D), (C)
• D. (C), (B), (D), (A)

Hint:

Biological nitrogen fixation for enriching soil with nitrogen, a key nutrient for plants, especially legumes.

Answer 1

The Correct Option is A

The correct sequence for biological nitrogen fixation is:
1. Rhizobium multiply to colonize the root.
2. Curling of root hair happens next.
3. Formation of infection thread follows.
4. Finally, differentiation of cortical cells into nitrogen-fixing cells occurs.