The production of which hormone increases when the frog is at a dark location

Options

A. Insulin
B. Oestrogen
C. MSH
D. None of these

Explanation

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks which hormone's production increases when a frog is in a dark location.

2. **Identifying the Hormones**: We have four options to consider:
- Option 1: Insulin
- Option 2: Estrogen
- Option 3: MSH (Melanocyte-Stimulating Hormone)
- Option 4: None of these

3. **Analyzing Each Option**:
- **Insulin**: This hormone is produced by the pancreas and is responsible for lowering blood glucose levels. It is not related to the frog's response to darkness.
- **Estrogen**: This is a steroid hormone primarily involved in the reproductive system and does not have a direct connection to light conditions in frogs.
- **MSH (Melanocyte-Stimulating Hormone)**: This hormone is produced by the pituitary gland and is responsible for stimulating the production of melanin in skin cells. In darker environments, the production of MSH increases to enhance pigmentation.
- **None of these**: This option suggests that none of the listed hormones are correct, which we will determine after analyzing the others.

4. **Conclusion**: Since MSH is known to increase in response to darkness to enhance pigmentation, it is the correct answer. Therefore, the production of MSH increases when the frog is in a dark location.

5. **Final Answer**: The hormone whose production increases when the frog is at a dark location is **MSH (Melanocyte-Stimulating Hormone)**.

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