Pineal gland of human brain secrets melatonin concerned with

Options

A. Colouration of skin
B. Sleep
C. Anger
D. Body temperature.

Answer

**Step-by-Step Solution:**

1. **Identify the Gland**: The question refers to the pineal gland, which is a small, pea-shaped gland located in the brain.

2. **Understand the Function**: The primary function of the pineal gland is the secretion of the hormone melatonin.

3. **Know the Role of Melatonin**: Melatonin is crucial for regulating sleep patterns. It helps control the circadian rhythm, which is the body's internal clock that dictates sleep-wake cycles.

4. **Light Exposure Influence**: The secretion of melatonin is influenced by light exposure. During the day, when there is more light, melatonin levels are lower, and as darkness increases, melatonin production increases.

5. **Conclusion**: Based on the information, the correct answer to the question regarding what melatonin is concerned with is "sleep."

**Final Answer**: The pineal gland of the human brain secretes melatonin, which is concerned with sleep.

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