Question

It is a butterfly-shaped mass present in the spinal cord :

• A. Grey matter
• B. White matter
• C. Dorsal root
• D. Ventral root

Answer 1

The correct option is A

Grey matter

The correct option is Option A

Explanation for the correct option:

1. Grey matter is present in the centre of the spinal cord in the shape of the alphabet ‘H’ or like the wings of the butterfly.
2. The grey matter of the spinal cord is distributed in three grey columns- (i) Dorsal horn or posterior grey column, (ii) Ventral horn or anterior grey column, and (iii) lateral grey column or lateral horn.

Explanation for the incorrect options:

Option B:

1. White matter refers to the regions with abundance of neuronal axons or nerve fibres.
2. In the spinal cord white matter covers grey matter.
3. White matter is present at the periphery of the spinal cord.

Option C:

1. In the spinal cord, grey matter is distributed in three grey columns- i. Posterior grey column ii. Anterior grey column root and iii. Lateral column.
2. The root of the spinal nerve comes out from the posterior grey column of the spinal cord and is known as the dorsal root.
3. This dorsal root comes out from the spinal cord (posterior or dorsal region of the spinal cord) and passes through the dorsal root ganglion.
4. It carries sensory information to the spinal cord.

Option- D:

1. The root of the spinal nerve comes out from the anterior grey column of the spinal cord and is known as the ventral root.
2. It is the motor root of the spinal nerve.
3. It carries motor information from the spinal cord.

Final answer: The butterfly-shaped mass present in the spinal cord is grey matter.