Parathormone regulates :

Options

A. Blood calcium level
B. Calcium phosphate level
C. Body temperature
D. None

Answer

**Step-by-Step Solution:**

1. **Identify the Source of Parathormone:**
- Parathormone, also known as parathyroid hormone (PTH), is secreted by the parathyroid glands. These glands are located on the backside of the thyroid gland.

2. **Understand the Function of Parathormone:**
- The primary function of parathormone is to regulate calcium levels in the blood. It is classified as a hypercalcimic hormone, meaning it increases the concentration of calcium ions in the blood.

3. **Effects on Blood Calcium Levels:**
- Parathormone increases the level of calcium in the blood. It does this by stimulating the release of calcium from bones into the bloodstream (bone resorption).

4. **Effects on Blood Phosphate Levels:**
- In addition to increasing calcium levels, parathormone decreases the level of phosphate in the blood. It promotes the excretion of phosphate through the kidneys.

5. **Absorption of Calcium:**
- Parathormone also enhances the absorption of calcium ions from the food we digest, further contributing to increased blood calcium levels.

6. **Conclusion on Regulation:**
- Therefore, parathormone regulates both calcium and phosphate levels in the body. The correct answer to the question is that parathormone regulates calcium and phosphate levels.

**Final Answer:**
Parathormone regulates calcium and phosphate levels in the body.

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