Peripheral nervous system

PNS features

* 12 pairs of cranial nerves connected to the brain which can be motor, sensory or mixed nerves
* 31 pairs of spinal nerves which enter and leave the spinal cord between successive vertebrae and they are ALL mixed nerves

PNS functions

1. Collects information from receptors and transmits this information by way of impulses along sensory afferent neurons to the CNS sensory function
2. Transmits impulses from the CNS by way of motor efferent neurons to effectors to bring about an appropriate response

Division of the PNS

1. SNS - somatic nervous system
* conducts impulses from the CNS to skeletal muscles and therefore controls all voluntary movements
2. ANS - autonomic nervous system
* conducts impulses from the CNS to cardiac muscle, smooth muscle and glands therefore controls all involuntary functions of muscles and glands

what is the ANS made up of?

1. Sympathetic nervous system
* works with adrenalin and when stimulated these nerves release more oxygen, glucose and blood to the skeletal muscles for a flight or fright response
2. Parasympathetic nervous system
* enables the body to recover from sympathetic stimulation and return to normal