Hormones involved in carbohydrate metabolism are

Options

A. Insulin, glucagon, epinephrine, and parathormone
B. Insulin, glucagon, epinephrine, and glucocorticoids
C. Insulin, glucagon, glucocorticoids, and calcitonin
D. Insulin, glucagon, nor-epinephrine, and melatonin

Answer

### Step-by-Step Solution:

1. **Identify the Hormones**: The question asks for hormones involved in carbohydrate metabolism. The key hormones to consider are insulin, glucagon, epinephrine, and glucocorticoids.

2. **Insulin**:
- Insulin is secreted by the beta cells of the islets of Langerhans in the pancreas.
- It facilitates the uptake of glucose by cells, thus lowering blood glucose levels.

3. **Glucagon**:
- Glucagon is secreted by the alpha cells of the islets of Langerhans in the pancreas.
- It increases blood glucose levels by promoting glycogenolysis, which converts glycogen to glucose.

4. **Epinephrine (Adrenaline)**:
- Secreted by the adrenal medulla, epinephrine plays a role in the body’s fight-or-flight response.
- It increases blood glucose levels by stimulating glycogen breakdown in the liver.

5. **Glucocorticoids**:
- These hormones are secreted by the adrenal cortex and are involved in regulating carbohydrate metabolism.
- They promote gluconeogenesis and glycogen formation, thus playing a significant role in maintaining blood glucose levels.

6. **Hormones Not Involved in Carbohydrate Metabolism**:
- Parathormone (secreted by the parathyroid gland) regulates calcium and phosphate levels but does not directly influence carbohydrate metabolism.
- Calcitonin (also not involved in carbohydrate metabolism) regulates calcium levels in the blood.
- Melatonin (secreted by the pineal gland) regulates circadian rhythms and is not involved in carbohydrate metabolism.

7. **Conclusion**:
- The hormones primarily involved in carbohydrate metabolism are insulin, glucagon, epinephrine, and glucocorticoids.
- Therefore, the correct answer includes insulin, glucagon, and glucocorticoids, while excluding parathormone, calcitonin, and melatonin.

### Final Answer:
The hormones involved in carbohydrate metabolism are **insulin, glucagon, epinephrine, and glucocorticoids**.

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