Question

Which one of the following is an innermost membrane that covers the brain?

• A. Arachnoid
• B. Duramater
• C. Piamater
• D. grey matter

Answer 1

The correct option is C

Piamater

The correct option is C:

Explanation for the correct option:

1. The central nervous system (Brain & spinal cord) is covered with three connective tissue layers called meninges.
2. The outermost layer of meninges is the dura mater, the middle layer is the arachnoid mater and the innermost layer is the pia mater.
3. Pia is the most delicate layer of meninges.

Explanation for the incorrect options:

Option A:

1. The Arachnoid mater is the middle layer of the meninges.
2. The space between the dura mater and arachnoid mater is called subdural space.
3. The space between the arachnoid mater and the pia mater is called subarachnoid space.
4. Cerebrospinal fluid is present inside the subarachnoid space.

Option B:

1. Dura mater is the outermost layer of the meninges.
2. This layer is made up of tough connective tissue (fibroblasts and a layer of extracellular collagen).

Option D:

1. Grey matter is the part of the CNS where the cell body of numerous neurons concentrate, this accounts for the grey appearance.
2. Human CNS (Central nervous system) has grey matter and white beneath the layer of meninges.
3. In the brain, the white matter lies beneath the grey matter and in the spinal cord grey matter lies beneath the white matter.

Final Answer: The delicate pia mater is the innermost layer of the brain cover (meninges).