Question

Assertion :

Some areas of the brain and spinal cord look white

Reason:

This is because cell bodies of neurons are situated in those areas.

• A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
• B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
• C. Assertion is correct but Reason is incorrect
• D. Both Assertion and Reason are incorrect

Answer 1

The correct option is C Assertion is correct but Reason is incorrect

• The brain and the spinal cord constitute the central nervous system. The areas of the CNS where the cell bodies of the neurons are situated, look grey and constitute the grey matter.
• Other areas look white and constitute the white matter of the CNS. The white matter contains only nerve fibers cruising from or to the nerve cells in the grey matter. It looks white due to the presence of myelin around the myelinated fibers.
• In most parts of the brain, the grey matter contains the nerve cells is situated on the surface while the white matter made of fibers is located deep inside the brain; but in the spinal cord, the grey matter is internal and white matter occurs outside.

So the correct answer is 'C'.