Question

Acetylene reduction test is used for the estimation of which one of the following?

• A. N$_2$
• B. C$_2$H$_2$
• C. CH$_4$
• D. SO$_2$

Hint:

Acetylene reduction assay:
- Measures nitrogenase activity.
- Acetylene (C$_2$H$_2$) $\rightarrow$ Ethylene (C$_2$H$_4$).
- Used to estimate biological nitrogen fixation.

Answer 1

The Correct Option is A

Step 1: Understanding the Question:
This question tests knowledge of the acetylene reduction assay for nitrogen fixation.

Step 2: Detailed Explanation:
The acetylene reduction test is used for the estimation of nitrogen fixation (N$_2$) (A).
Nitrogenase enzyme reduces acetylene (C$_2$H$_2$) to ethylene (C$_2$H$_4$).
The amount of ethylene produced is proportional to nitrogenase activity and nitrogen fixation.
Other options:
- C$_2$H$_2$ (B): The substrate, not the estimation target.
- CH$_4$ (C): Not related.
- SO$_2$ (D): Not related.
Thus, the test estimates nitrogen fixation (N$_2$).

Step 3: Final Answer:
Thus, the acetylene reduction test is used for the estimation of N$_2$, which corresponds to option (A).
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