The nervous system is divided into two parts, the peripheral nervous system (PNS) and the central nervous system.
The peripheral nervous system is formed by:
Neurons of cranial and spinal nerve.
The central nervous system is formed by: Neurons of the spinal cord, brain stem, Cerebellum, and cerebrum.
The other parts of the nervous system are:
- Neurons
- Sensory receptors and Special Senses
- Nerves or Nerves bundle
- Spinal Cord
- Brain
Neurons: the nerve cells of neurons is the basic functional unit of nervous system
Sensory Receptors and Special Senses: they take up changes in homeostatic norms and activate nerves.
Nerves/Nerve bundles: They function as messengers, Carry messages to and from specific muscles, organs, etc. and the spinal cord.
Spinal Cord: composed of neurons which works as a messenger and carry messages to and from the brain.
Brain: Integrates and organizes the afferent input to determine appropriate efferent response.