Carbohydrate metabolism is controlled by

Options

A. parathormone
B. Insulin
C. Glucose
D. Vitamin `B_(12)`

Answer

**Step-by-Step Solution:**

1. **Understanding Carbohydrate Metabolism**: Carbohydrate metabolism refers to the biochemical processes that break down carbohydrates into glucose, which is then used for energy by the body.

2. **Identifying Hormones Involved**: The metabolism of carbohydrates is regulated by various hormones produced by the endocrine system. The question asks which specific hormone controls carbohydrate metabolism.

3. **Evaluating the Options**:
- **Parathormone**: This hormone, also known as parathyroid hormone, is primarily involved in regulating calcium levels in the blood, not carbohydrate metabolism.
- **Insulin**: This hormone is secreted by the pancreas and plays a crucial role in regulating blood glucose levels. It signals cells to take in glucose from the bloodstream, thus controlling carbohydrate metabolism.
- **Glucose**: This is the end product of carbohydrate metabolism, not a regulator of it.
- **Vitamin B12**: This vitamin is important for maintaining normal blood levels of calcium and phosphorus but does not directly regulate carbohydrate metabolism.

4. **Conclusion**: Based on the evaluation of the options, insulin is the hormone that controls carbohydrate metabolism by regulating blood glucose levels.

5. **Final Answer**: Insulin

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