Which gland responsible for calcium metabolism-

Options

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

Explanation

**Step-by-Step Solution:**

1. **Identify the Glands Listed:**
- The question presents four glands: thymus, thyroid, parathyroid, and adrenals.

2. **Understand the Function of Each Gland:**
- **Thymus:** Secretes thymosine, which is involved in immune function.
- **Thyroid:** Produces thyroxin, which regulates metabolism.
- **Parathyroid:** Secretes parathyroid hormone (PTH), which is crucial for calcium metabolism.
- **Adrenals:** Produce hormones related to stress response and metabolism, but not specifically calcium.

3. **Focus on Calcium Metabolism:**
- Calcium metabolism is primarily regulated by the parathyroid hormone (PTH).
- PTH increases blood calcium levels, making it essential for calcium homeostasis.

4. **Eliminate Incorrect Options:**
- Thymus is related to immunity, not calcium.
- Thyroid is related to metabolic rate, not directly to calcium.
- Adrenals do not play a role in calcium metabolism.

5. **Conclude the Correct Answer:**
- The parathyroid gland is responsible for calcium metabolism through the secretion of PTH.

**Final Answer:**
The gland responsible for calcium metabolism is the **parathyroid gland**.

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