Nerve cell

A nerve cell consists of a cell body with dendrites and a nucleus, an axon which is surrounded by a myelin sheath which passes the nervous signal along to axon terminals. Synapses with other cells occur at the dendrites and axon terminals, stimuli (e.g. chemical or electrical) cause the nerve to depolarise and an action potential is produced. Once at the axon terminals the signal can be transferred to neighbouring nerve cells or effector cells by a chemical neurotransmitter e.g. acetylcholine. A high temperature, large axon diameter and the presence of a myelin sheath increase the rate at which the signal is transmitted along the axon.