Name the non-iodinized hormone secreted by paraforllicular cells of thyroid.

Options

A. Calcitonin
B. Oxytocin
C. Vasopressin
D. Gonadotropin

Answer

**Step-by-Step Text Solution:**

1. **Identify the Cells**: The question asks for the non-iodinized hormone secreted by parafollicular cells of the thyroid. Parafollicular cells are also known as C cells.

2. **Understand the Function of Parafollicular Cells**: These cells are located in the thyroid gland and are responsible for producing hormones that do not require iodine for their synthesis.

3. **List the Options**: The options provided are calcitonin, oxytocin, vasopressin, and gonadotropin.

4. **Analyze the Options**:
- **Calcitonin**: This hormone is produced by the parafollicular cells and is involved in regulating calcium levels in the blood.
- **Oxytocin**: This hormone is produced by the posterior pituitary gland and is not related to the thyroid.
- **Vasopressin**: Also known as antidiuretic hormone (ADH), it is secreted by the posterior pituitary gland and is not related to the thyroid.
- **Gonadotropin**: This hormone is produced by the anterior pituitary gland and is not related to the thyroid.

5. **Conclusion**: Among the options, calcitonin is the only hormone that is secreted by the parafollicular cells of the thyroid and is non-iodinized.

6. **Final Answer**: The non-iodinized hormone secreted by parafollicular cells of the thyroid is **calcitonin**.

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