Sleep -wake cycle,menstrual cycle are influenced by

Options

A. thyroxine
B. calcutonin
C. FSH
D. melatonin

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the factors influencing the sleep-wake cycle and menstrual cycle.

2. **Identifying the Cycles**:
- The **sleep-wake cycle** is a 24-hour cycle that regulates when we sleep and when we are awake.
- The **menstrual cycle** is a monthly cycle that prepares the female body for potential pregnancy.

3. **Hormonal Influence**: Both cycles are regulated by hormones. To determine which hormone is responsible, we need to analyze the options provided.

4. **Evaluating the Options**:
- **Option A: Thyroxine** - This hormone primarily regulates metabolism and is not directly involved in the sleep-wake cycle or menstrual cycle.
- **Option B: Calcium tonic** - This is not a hormone and does not influence these cycles.
- **Option C: FSH (Follicle Stimulating Hormone)** - While it plays a role in the menstrual cycle, it does not regulate the sleep-wake cycle.
- **Option D: Melatonin** - This hormone is produced by the pineal gland and is known as the "sleep hormone." It regulates sleep patterns by being released in higher amounts at night, promoting sleep, and in lower amounts during the day, promoting wakefulness.

5. **Conclusion**: Based on the evaluation, the hormone that influences both the sleep-wake cycle and the menstrual cycle is **melatonin**. Therefore, the correct answer is **Option D**.

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