Question

Given below are two statements:
Statement I: Nitrate assimilation in plants occurs only in roots.
Statement II: Plants transport the nitrite generated by nitrate reduction, immediately, from the cytosol into chloroplast because it is potentially toxic to the cells.
In the light of the above statements, choose the most appropriate answer from the options given below:

• A. Both Statement I and Statement II are correct
• B. Both Statement I and Statement II are incorrect
• C. Statement I is correct but Statement II is incorrect
• D. Statement I is incorrect but Statement II is correct

Hint:

Nitrate reduction occurs in both roots and shoots.
Nitrite is toxic and quickly transported to chloroplasts.
Nitrite reductase reduces nitrite to ammonium.

Answer 1

The Correct Option is D

Step 1: Understanding the Question:
Nitrate assimilation involves the reduction of nitrate to nitrite and then to ammonium.
This process is essential for plant growth and nitrogen metabolism.

Step 2: Detailed Explanation:
Statement I:
Nitrate assimilation occurs in both roots and shoots (leaves).
In many plants, nitrate is reduced in the leaves, not only in roots.
This statement is false.
Statement II:
Nitrite is toxic to cells at high concentrations.
It is immediately transported from the cytosol into chloroplasts (or plastids) where it is further reduced to ammonium by nitrite reductase.
This statement is true.

Step 3: Final Answer:
Thus, Statement I is incorrect but Statement II is correct, which corresponds to option (D).
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