The Divisions of the Nervous System

The divisions of the nervous system are the central nervous system and the peripheral nervous system.

The central nervous system consists of the brain and the spinal cord.

The peripheral nervous system includes everything outside of the central nervous system, including the somatic nervous system and the autonomic nervous system.

Somatic nervous system and autonomic nervous system

To initiate the 'fight or flight' response

To regulate the body's rest and digest response

The two main divisions of the nervous system are the central nervous system (CNS) and the peripheral nervous system (PNS).

The peripheral nervous system consists of the somatic nervous system, which controls voluntary actions, and the autonomic nervous system, which controls involuntary actions.

The sympathetic nervous system is responsible for the 'fight or flight' response, preparing the body for emergencies. The parasympathetic nervous system helps to restore the body to a calm state after the stress response.

The two branches of spinal nerves are the ventral root and the dorsal root. The ventral root contains axons of motor neurons, while the dorsal root contains axons of sensory neurons.

The dorsal root ganglia contain the cell bodies of sensory neurons.

Spinal nerves are composed of both afferent (sensory) and efferent (motor) fibers, making them mixed nerves.

There are 12 pairs of cranial nerves connected to the brain.

The four classifications of cranial nerves are sensory nerves, special sensory nerves, motor nerves, and mixed nerves.