Biochemical phase in photosynthesis was discovered for the first time by using `C^(14)`

Options

A. Calvin
B. Blackman
C. Hill
D. Arnon

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the scientist who first discovered the biochemical phase of photosynthesis using the isotope Carbon-14 (C-14).

2. **Identifying the Biochemical Phase**: The biochemical phase of photosynthesis is primarily known as the Calvin cycle, which is a series of reactions that convert carbon dioxide and other compounds into glucose.

3. **Historical Context**: The Calvin cycle was discovered through the use of radioactive isotopes, specifically Carbon-14, which allowed scientists to trace the path of carbon in the photosynthetic process.

4. **Key Scientists**: The scientists associated with the discovery of the Calvin cycle include Melvin Calvin, Andrew Benson, and James Bassham. They conducted experiments using C-14 in the early 1950s.

5. **Conclusion**: Among the options provided, the correct answer is Melvin Calvin, who is credited with the discovery of the Calvin cycle using Carbon-14.

6. **Final Answer**: The biochemical phase in photosynthesis was discovered for the first time by Melvin Calvin using C-14.

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