The growth maintenance and functions of seminiferous tubules and Leydig cells are regulated respectively by

Options

A. LH and FSH
B. FSH and LH
C. Gonadotropins and testosterone
D. Testosterone and FSH

Answer

To answer the question regarding the regulation of the growth, maintenance, and functions of seminiferous tubules and Leydig cells, we can break down the information step by step.

### Step-by-Step Solution:

1. **Identify the Structures**:
- The seminiferous tubules are located in the testes and are responsible for spermatogenesis, which is the production of sperm.
- Leydig cells, also known as interstitial cells, are located in the spaces between the seminiferous tubules and are responsible for producing testosterone.

2. **Understand the Hormones Involved**:
- The two main hormones that regulate the functions of the testes are Luteinizing Hormone (LH) and Follicle Stimulating Hormone (FSH).
- LH is primarily responsible for stimulating Leydig cells to produce testosterone.
- FSH is responsible for stimulating the seminiferous tubules to facilitate spermatogenesis.

3. **Determine the Correct Pairing**:
- The question asks for the regulation of the growth, maintenance, and functions of seminiferous tubules and Leydig cells respectively.
- Since LH stimulates Leydig cells to produce testosterone, and FSH stimulates the seminiferous tubules for spermatogenesis, the correct pairing is:
- Leydig cells are regulated by LH.
- Seminiferous tubules are regulated by FSH.

4. **Select the Correct Answer**:
- Based on the above analysis, the correct answer to the question is "FSH and LH".

### Final Answer:
The growth, maintenance, and functions of seminiferous tubules and Leydig cells are regulated respectively by FSH and LH.

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