Anatomy of a neuron

Anatomy of a neuron

  • Dendrites-receive incoming impulses

  • Cell Body(somas)

  • Axons-generate and send out impulses

    • Insulated Myelin sheaths(helps move more quickly)

    • Gaps are called nodes of ranvier

    • Made of schwann cells in PNS and oligodendrocytes in CNS


  • Axon terminals(nerve terminals)

    • Where neuron connections are


  • Synapse 

    • Is the point where neurons transfer impulses from cells


Types of Neurons

  • Multipolar

    • 1 axon

    • Several dendrites 

    • Most common

  • Bipolar

    • 1 axon and 1 dendrites at opposite ends

    • Rare structure

  • Unipolar

    • One process which splits in two

    • In PNS


  • Motor neurons(efferent neurons)

    • Carry impulses from CNS(brain and spinal cord) to effector organs(target organs like muscles, skin and glands)

    • Cause organs to function

    • Control most bodily functions

    • Typically Multipolar, cell bodies in CNS, and axons in PNS

  • Sensory neurons(afferent neurons)

    • Detect physical and chemical stimuli at receptors in the organs and conduct impulse to CNS

    • Mostly unipolar, cell bodies in PNS and axon terminals connecting with those neurons in CNS

    • Are bipolar in certain special sense organs(eyes)

SAME-Sensory neuron afferent, Motor neuron efferent

  • Interneurons (central or associative neurons)

    • Carry impulses between motor and sensory neurons

    • Located within central nervous system(90% of CNS is interneurons)

    • All multipolar