Grave's disease is due to :

Options

A. Hyperactivity of thyroid gland
B. Hyperactivity of adrenal cortex
C. Hyperactivity of adrenal medulla
D. Hypoactivity of Islets of Langerhans

Answer

**Step-by-Step Solution:**

1. **Understanding Grave's Disease:**
- Grave's disease is an autoimmune disorder that primarily affects the thyroid gland. In this condition, the immune system produces antibodies that mistakenly attack the thyroid gland.

2. **Effect on Thyroid Gland:**
- The attack on the thyroid gland leads to an increase in the production of thyroxine (T4), a hormone that regulates metabolism. This overproduction of thyroxine is what characterizes Grave's disease.

3. **Analyzing the Options:**
- **Option 1: Hyperactivity of the thyroid gland.**
- This option is correct because the hyperactivity of the thyroid gland results in excess thyroxine production, which is a key feature of Grave's disease.
- **Option 2: Hyperactivity of Adrenal Cortex.**
- This option is incorrect. The adrenal cortex is responsible for producing hormones related to stress response and metabolism, not directly related to Grave's disease.
- **Option 3: Hyperactivity of the Adrenal Medulla.**
- This option is also incorrect. The adrenal medulla produces adrenaline and noradrenaline, which are not involved in the pathology of Grave's disease.
- **Option 4: Hypoactivity of Islets of Langerhans.**
- This option is incorrect as well. The Islets of Langerhans are involved in insulin production and glucose regulation, which is not related to the thyroid dysfunction seen in Grave's disease.

4. **Conclusion:**
- Based on the analysis, the correct answer to the question "Grave's disease is due to:" is **hyperactivity of the thyroid gland**.

**Final Answer:**
Grave's disease is due to hyperactivity of the thyroid gland.

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