The function of pineal body is to

Options

A. regulates the peroid of puberty
B. maintains sleep awake cycle
C. lighten the skin colours
D. all of the above

Answer

### Step-by-Step Solution

1. **Identify the Pineal Body**: The pineal body, also known as the pineal gland, is a small endocrine gland located in the brain.

2. **Understand its Main Function**: The primary function of the pineal body is to secrete the hormone melatonin.

3. **Role of Melatonin**: Melatonin plays several important roles:
- It helps regulate the sleep-wake cycle (circadian rhythms).
- It influences the timing of puberty by regulating the functioning of gonads (the sexual reproductive organs).
- In some animals, melatonin can affect skin pigmentation, making the skin lighter.

4. **Evaluate the Options**: The question provides multiple choices regarding the functions of the pineal body:
- Regulate the period of puberty
- Maintain the sleep-awake cycle
- Lighten the skin colors
- All of the above

5. **Select the Correct Answer**: Since the pineal body is involved in all the mentioned functions, the correct answer is "all of the above".

### Final Answer
The function of the pineal body is to **regulate the period of puberty, maintain the sleep-awake cycle, lighten the skin colors, and all of the above** (Option D).

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