The scientists to discover photophosphorylation was

Options

A. Arnon
B. Hill
C. Willstatter and Stoll
D. Park and Biggins.

Answer

**Step-by-Step Solution:**

1. **Understanding Photophosphorylation:**
- Photophosphorylation is the process of synthesizing ATP (adenosine triphosphate) from ADP (adenosine diphosphate) and inorganic phosphate (Pi) in the presence of light. This process occurs in the chloroplasts of plant cells.

2. **Types of Photophosphorylation:**
- There are two types of photophosphorylation: cyclic and non-cyclic photophosphorylation. Both processes involve the conversion of light energy into chemical energy in the form of ATP.

3. **Historical Context:**
- The discovery of photophosphorylation is attributed to the scientist Daniel Arnon in 1954. He conducted experiments that helped differentiate between cyclic and non-cyclic photophosphorylation and also compared photophosphorylation with oxidative phosphorylation.

4. **Comparison with Oxidative Phosphorylation:**
- In photophosphorylation, ATP is synthesized using light energy, while in oxidative phosphorylation, ATP is produced using chemical energy derived from the oxidation of nutrients.

5. **Conclusion:**
- The scientist who discovered photophosphorylation is Daniel Arnon. Therefore, the correct answer to the question is Daniel Arnon.

**Final Answer:**
The scientist to discover photophosphorylation was Daniel Arnon.

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