Which of the following structures contains groups of neurosecretory cells?

Options

A. Hypothalamus
B. Cerebral cortex
C. Thalamus
D. Piamater

Answer

To determine which structure contains groups of neurosecretory cells, we will analyze the given options: hypothalamus, thalamus, cerebrum, and pia mater.

### Step-by-Step Solution:

1. **Understanding Neurosecretory Cells**: Neurosecretory cells are specialized neurons that produce and secrete hormones. They play a crucial role in the endocrine system by regulating various bodily functions.

2. **Analyzing the Options**:
- **Pia Mater**: This is the innermost layer of the meninges that surrounds the brain. Its primary function is protective, acting as a cushion for the brain. It does not contain neurosecretory cells.
- **Cerebrum**: This is the largest part of the brain responsible for complex functions such as thought, memory, and sensory processing. While it contains many types of neurons, it is not primarily known for neurosecretory cells.
- **Thalamus**: This structure acts as a relay station for sensory information and is involved in various functions, but it does not primarily function as a site for neurosecretory cells.
- **Hypothalamus**: Located at the base of the thalamus, the hypothalamus is a critical structure in the brain that has both neural and endocrine functions. It contains groups of neurosecretory cells known as nuclei, which produce and secrete hormones that regulate the pituitary gland's activity.

3. **Conclusion**: The structure that contains groups of neurosecretory cells is the **hypothalamus**. It plays a vital role in hormone secretion and regulation of the endocrine system.

### Final Answer:
**Hypothalamus**

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