Question

The grey colour of the cerebral cortex is due to

• A. neuronal cell bodies
• B. neuronal myelinated axons
• C. neuronal unmyelinated axons
• D. both a and c

Answer 1

The correct option is D both a and c

The brain and the spinal cord are parts of the central nervous system. The brain is divided into forebrain, midbrain and the hindbrain.
The forebrain is further divided into cerebrum , thalamus and hypothalamus. The outer layer of the cerebrum is called cerebral cortex or the grey matter. The grey matter is mainly composed of neuronal cell bodies and unmyelinated axons.
The inner layer of the cerebral cortex is called white matter. White matter areas of the brain mainly consist of myelinated axons, which are long relays that extend out from the soma or the neuronal cell bodies from the grey matter. They are whitish in color due to the relatively high lipid fat content of the myelin that sheathes them.