The internal (cellular) energy reserve in autotrophs is

Options

A. glycogen
B. protein
C. starch
D. fatty acid

Explanation

**Step-by-Step Solution:**

1. **Understanding Autotrophs**: Autotrophs are organisms that can produce their own food. In the context of biology, this primarily refers to plants, which use photosynthesis to convert sunlight, carbon dioxide, and water into glucose.

2. **Photosynthesis Process**: During photosynthesis, plants convert light energy into chemical energy stored in glucose. This process occurs in the chloroplasts of plant cells, where chlorophyll captures sunlight.

3. **Energy Usage and Storage**: The glucose produced during photosynthesis is used by plants for energy to carry out various life processes. However, not all of the glucose is consumed immediately.

4. **Storage of Excess Energy**: The excess glucose that is not used for immediate energy needs is converted into a storage form. In plants, this storage form is starch.

5. **Identifying the Energy Reserve**: Starch serves as the internal cellular energy reserve in autotrophs. It is a polysaccharide that plants synthesize and store in various parts, such as roots, stems, and leaves.

6. **Conclusion**: Therefore, the internal (cellular) energy reserve in autotrophs is starch.

**Final Answer**: The internal (cellular) energy reserve in autotrophs is **starch**.

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