Serotonin and Melatonin are hormones, secreted by

Options

A. Thymus
B. Pineal
C. Thyroid
D. Adrenal.

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the glands that secrete the hormones serotonin and melatonin.

2. **Analyzing the Options**: The options provided are:
- 1st: Thymus
- 2nd: Pineal
- 3rd: Thyroid
- 4th: Adrenal

3. **Evaluating Each Option**:
- **Thymus**: The thymus gland is known for producing thymosine, which is important for T cell development. It does not secrete serotonin or melatonin. Therefore, this option is incorrect.

- **Pineal**: The pineal gland is located in the center of the brain and is responsible for the secretion of melatonin. Serotonin is a precursor to melatonin, meaning serotonin is converted into melatonin in the pineal gland. Thus, this option is correct.

- **Thyroid**: The thyroid gland primarily secretes hormones like thyroxine (T4) and triiodothyronine (T3). It does not secrete serotonin or melatonin, making this option incorrect.

- **Adrenal**: The adrenal glands secrete hormones such as cortisol and aldosterone. They do not produce serotonin or melatonin, so this option is also incorrect.

4. **Conclusion**: After evaluating all options, the correct answer is that serotonin and melatonin are secreted by the **pineal gland**.

**Final Answer**: Pineal gland

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