Unit 5: The nervous and endocrine systems                    1   2   3   4   5

4. The perypheral nervous system

It is formed by nerves which connect the CNS with the receptors and effectors.

A nerve is an association of myelinated axons involved in connective tissue.

Many nerves have ganglia. A ganglion is a relay point of the nerve impulse. It contains the dendrites and soma of a postsynaptic neuron.

  The PNS can be divided into two functional subsystems:

-The somatic nervous system. It is the part of the peripheral nervous system that controls the voluntary movement of skeletal muscles.

-The autonomic nervous system. It is the part of the peripheral nervous system that controls the visceral functions. Most of its actions are involuntary and unconscious.  

4.1. What criterion do we follow to divide the peripheral nervous system

             into somatic and autonomic nervous system?