The scientist who proposed the product of photosynthesis is starch in illuminated chloroplasts was

Options

A. Sachs
B. Menke
C. Schimper
D. Von Mayer

Answer

To answer the question regarding the scientist who proposed that the product of photosynthesis in illuminated chloroplasts is starch, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Key Concept**: The question is asking about the scientist who identified starch as the product of photosynthesis in chloroplasts when they are illuminated.

2. **Research Historical Contributions**: Look into the contributions of various scientists to the field of photosynthesis. Notable figures include Sachs, Schimper, and von Meyer.

3. **Focus on Sachs**: Among these scientists, it was Julius von Sachs who is credited with the discovery that starch is produced during photosynthesis in chloroplasts when exposed to light.

4. **Clarify Other Contributions**: While other scientists like Schimper and von Meyer made significant contributions to the understanding of chloroplasts and photosynthesis, it was Sachs who specifically linked starch production to the process of photosynthesis in illuminated chloroplasts.

5. **Conclude with the Correct Answer**: Therefore, the correct answer to the question is Julius von Sachs.

### Final Answer:
The scientist who proposed that the product of photosynthesis in illuminated chloroplasts is starch is Julius von Sachs.

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