Which of the following is under the direct connrol of neurosecretory cells?

Options

A. Pars distalis and pars intermedia
B. Pars intermedia and pars nervosa
C. Pars nervosa only
D. Pars distalis only

Answer

To solve the question "Which of the following is under the direct control of neurosecretory cells?", we will analyze the options provided and understand the relationship between neurosecretory cells and the parts of the pituitary gland.

### Step-by-Step Solution:

1. **Understanding Neurosecretory Cells**:
- Neurosecretory cells are specialized neurons that produce hormones and release them into the blood. They play a crucial role in the endocrine system by linking the nervous system to the hormonal system.

2. **Identifying the Parts of the Pituitary Gland**:
- The pituitary gland is divided into three parts:
- Pars distalis (anterior pituitary)
- Pars intermedia (middle part)
- Pars nervosa (posterior pituitary)

3. **Analyzing the Direct Control**:
- Neurosecretory cells are primarily associated with the posterior pituitary (pars nervosa). They extend from the hypothalamus and release hormones directly into the bloodstream at this site.

4. **Evaluating Each Option**:
- **Option 1: Pars distalis and pars intermedia**: These parts are controlled indirectly by hormones released from the hypothalamus, not directly by neurosecretory cells.
- **Option 2: Pars intermedia and pars nervosa**: While pars nervosa is directly controlled, pars intermedia is not directly connected to neurosecretory cells.
- **Option 3: Pars nervosa only**: This is the correct option as neurosecretory cells have a direct connection with this part.
- **Option 4: Pars distalis only**: This part is also not directly controlled by neurosecretory cells.

5. **Conclusion**:
- The correct answer is **Option 3: Pars nervosa only**, as it is the only part of the pituitary gland that is under the direct control of neurosecretory cells.

### Final Answer:
**Option 3: Pars nervosa only**