Question

The below diagram represents the human brain as seen in an external view. Study the same and then answer the questions that follow:

(i) Name the parts labeled 1, 2, 3 and 4.

(ii) Mention the difference in the arrangement of the nerve cells in the parts marked ‘1’ and ‘4’.

(iii) What is the main function of the parts marked ‘3’ and ‘4’?

(iv) Name the sheet of nerve fibres that connect the two halves of the part labeled ‘1’.

Answer 1

(i) 1. Cerebrum,

1. Cerebellum,

2. Medulla oblongata,

3. Spinal cord.

(ii) 1. Grey matter is outside and white matter inside.

1. White matter * outside and gray matter is inside.

(iii) 3. Medulla oblongata controls all involuntary movements of internal organs e.g., breathing movements of lungs, beating of heart.

1. Spinal cord performs reflex action below the neck.

(iv) Corpus callosum.