The calcium level is increased in blood by promoting

Options

A. Dissolution of skeletal structures
B. Excretion of calcium in urine
C. Mineralisation of bones
D. Mineralisation of teeth

Answer

To solve the question regarding how calcium levels are increased in the blood, we can break it down into the following steps:

### Step-by-Step Solution:

1. **Understand the Role of Hormones**:
- The calcium level in the blood is regulated by two key hormones: parathormone (PTH) and thyrocalcitonin (calcitonin).
- Parathormone is secreted by the parathyroid glands, while thyrocalcitonin is secreted by the thyroid gland.

2. **Function of Parathormone**:
- Parathormone increases the calcium level in the blood. It does this by stimulating the release of calcium from the bones.
- When calcium levels in the blood are low, parathormone promotes the demineralization of the bone, releasing calcium into the bloodstream.

3. **Function of Thyrocalcitonin**:
- Thyrocalcitonin acts as an antagonist to parathormone. It decreases the calcium level in the blood by promoting the deposition of calcium in the bones.
- This means that when thyrocalcitonin is active, it works to lower blood calcium levels by encouraging mineralization.

4. **Analyzing the Options**:
- **Desalination of skeletal structure**: This refers to the process of demineralization, where calcium is released from the bones into the blood. This action increases blood calcium levels, making this option correct.
- **Excretion of calcium in urine**: This would decrease blood calcium levels, so this option is incorrect.
- **Mineralization of bones**: This involves depositing calcium into the bones, which would lower blood calcium levels, making this option incorrect.
- **Mineralization of teeth**: Similar to bone mineralization, this would also lower blood calcium levels, making this option incorrect.

5. **Conclusion**:
- The correct answer is that the calcium level is increased in the blood by promoting the **desalination of skeletal structure** (demineralization).

### Final Answer:
The calcium level is increased in blood by promoting **desalination of skeletal structure**.

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