Question

Why do you call the spinal cord and the brain as the central nervous system?

Answer 1

Central nervous system/CNS:

1. The CNS is made up of the brain and spinal cord which are enclosed by three layers called the meninges.
2. The layers of the meninges include the dura mater, arachnoid mater, and the pia mater from the exterior to the interior.
3. The shock-absorbing function of the CNS is performed by the cerebrospinal fluid located between the arachnoid and the pia mater.

Reason for being referred to as CNS:

1. The brain and spinal cord integrate the information received from the external environment via the sensory nerves.
2. They also coordinate the activities of the whole body of an organism by conducting motor information to the effector organs via the motor neurons.

Hence, the brain and the spinal cord are called the central nervous system as they integrate information got from the sensory receptors and coordinate activities of the organism through the motor nerves.