THE PERIPHERAL NERVOUS SYSTEM

The peripheral nervous system

It extends beyond the central nervous system and the role is to relay messages from the CNS (brain and spinal cord) to the rest of the body

What is the peripheral nervous system made up of

The somatic and autonomic nervous system

The somatic nervous system

It’s made up of nerves extending from the brain and spinal cord, as well as sensory receptors and motor pathwats

What is the somatic nervous system important for

Voluntary movement

What do the sensory receptors in the somatic nervous system do

They carry information to the brain and spinal cord

What do motor pathways in the somatic nervous system do

They allow the brain to control movement in muscles

The autonomic nervous system

Madd up of motor pathways and transmits messages to and from the internal organs and regulates involuntary actions like digestion, heart rate or breathing

What is the autonomic nervous system made up of

The sympathetic nervous system that generally increases body activities, and the parasympathetic nervous system that maintains or decreases body activity

The sympathetic nervous system

Primarily involved with dealing with emergencies such as fight or flight

What do neurons from the sympathetic nervous system do

They travel to organs and glands around the body and prepare the body for action. For example, in response to stress the heart rate and blood pressure will increase and the pupils will dilate. Processes like digestion are less important in emergencies so will be slowed down

The parasympathetic nervous system

This system is responsible for returning the body back to normal after fight or flight. The parasympathetic nervous system slows down our breathing rate, heart rate and blood pressure. Any functions that were previously slowed down are started again such as digestion