Assertion :- MSH & Melatonin are antagonistic hormones.
Reason:- MSH help in the wide distribution of melanin in melanocytes while melatonin collects the melanin at one place in melanocyte

Options

A. If both assertion and reason are true and reason is the correct explanation of assertion
B. If both assertion and reason are true but reason is not the correct explanation of assertion
C. If assertion is true but reason is false
D. If both assertion and reason are false.

Answer

To analyze the assertion and reason provided in the question, we can break down the concepts step by step:

### Step 1: Understand the Assertion
The assertion states that "MSH (Melanocyte-Stimulating Hormone) and Melatonin are antagonistic hormones."
- **Explanation**: Antagonistic hormones are those that have opposing effects on the same physiological process. In this case, MSH promotes the production and distribution of melanin in the skin and hair, while melatonin is known to regulate sleep and circadian rhythms, and its role in pigmentation is less direct.

### Step 2: Understand the Reason
The reason given is that "MSH helps in the wide distribution of melanin in melanocytes while melatonin collects the melanin at one place in melanocyte."
- **Explanation**: MSH indeed stimulates melanocytes to produce and distribute melanin, which darkens the skin. On the other hand, melatonin's role in pigmentation is more about regulating the overall process rather than physically collecting melanin. It does not directly cause melanin to be gathered in one place; rather, it influences pigmentation indirectly.

### Step 3: Evaluate the Relationship
Now, we need to evaluate if the reason correctly explains the assertion.
- **Analysis**: While both statements are true regarding the functions of MSH and melatonin, the reason does not accurately explain why they are considered antagonistic. The assertion is correct, but the reason misrepresents the role of melatonin.

### Conclusion
Based on the analysis:
- The assertion is true: MSH and melatonin can be considered antagonistic in their effects on pigmentation.
- The reason is true but does not correctly explain the assertion.

Thus, the correct answer is that the assertion is true, and the reason is false.

### Final Answer
**Assertion is true, and reason is false.**

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