Reproductive organs mature and produce sex cells only at a certain age. The growth and maintenance of the reproductive system is essential for reproduction. The growth and maintenance of the reproductive system is under the control of

Options

A. pancreas
B. thyroid gland
C. hypothalamus
D. pituitary gland

Answer

### Step-by-Step Solution:

1. **Understanding the Reproductive System**: The reproductive organs, known as gonads, are responsible for producing sex cells (gametes) and maturing at a certain age. This process is crucial for reproduction.

2. **Identifying the Control Mechanism**: The growth and maintenance of the reproductive system is regulated by specific glands in the body. The question asks which gland controls this process.

3. **Evaluating the Options**:
- **Pancreas**: This gland is primarily involved in regulating blood glucose levels through insulin and glucagon. It does not control the reproductive system.
- **Thyroid Gland**: Located in the neck, it produces hormones (T3 and T4) that regulate metabolism, not reproduction.
- **Hypothalamus**: This part of the brain produces hormones that control the pituitary gland, including releasing and inhibitory hormones.
- **Pituitary Gland**: This gland releases hormones that directly affect the gonads (LH and FSH), but it is regulated by the hypothalamus.

4. **Conclusion**: The hypothalamus is the primary control center for the reproductive system. It releases gonadotropin-releasing hormone (GnRH), which stimulates the pituitary gland to release LH and FSH. These hormones then act on the gonads to regulate their function.

5. **Final Answer**: The growth and maintenance of the reproductive system is under the control of the **hypothalamus**.