In the central nervous system myelinated fibres form the …. While the non-myelinated fibre cells form the …….

Options

A. Grey matter , white matter
B. White matter , grey matter
C. Ependymal cells , neurosecretory cells
D. Neurosecretory cells , ependymal cells

Answer

To answer the question, "In the central nervous system myelinated fibres form the …. While the non-myelinated fibre cells form the ….", we need to understand the structure and function of nerve fibers in the central nervous system (CNS).

### Step-by-Step Solution:

1. **Understanding Myelination**: Myelinated fibers in the CNS are those that are covered by a myelin sheath. This sheath is essential for the rapid transmission of electrical impulses along the nerve fibers.

2. **Identifying Myelinated Fibers**: In the CNS, myelinated fibers primarily make up the **white matter**. White matter is characterized by its lighter appearance due to the presence of myelin, which surrounds the axons of neurons.

3. **Understanding Non-Myelination**: Non-myelinated fibers, on the other hand, lack this myelin sheath. These fibers consist mainly of nerve cell bodies and dendrites.

4. **Identifying Non-Myelinated Fibers**: In the CNS, non-myelinated fibers form the **grey matter**. Grey matter is darker in appearance and is involved in processing and integrating information.

5. **Conclusion**: Therefore, we can conclude that in the central nervous system, myelinated fibers form the **white matter**, while non-myelinated fiber cells form the **grey matter**.

### Final Answer:
In the central nervous system, myelinated fibres form the **white matter** while the non-myelinated fibre cells form the **grey matter**.

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