The structure of neurons
Label
Function/Description
Sensory neuron
Transmits impulses from sensory receptors to CNS.
Motor neuron
Transmits impulses from CNS to muscles and glands.
Interneuron
Also called association or relay neurons located in the CNS
and transmits signals between sensory and motor neurons.
Cell body
Contains the nucleus and organelles of the cell to control
normal functioning.
Axon
Single, thin extension of the neuron that conducts impulses
away from the cell body.
Dendrite
Thin extensions of the neuron that receives impulses and
directs them towards the cell body.
Dendron
Single dendrite found on a sensory neuron that transmits
impulses towards the cell body from the receptors.
Receptor
(sense organ)
Specialised cells located around the body that transmit stimuli
through sensory neurons to the CNS.
Myelin sheath
Fatty insulative layer, formed by Schwann Cells, that can
surround a dendrite or axon and functions to increase the
speed of a nerve impulse.
Node of Ranvier
Gaps between the myelin sheath of an Axon or dendrite that
prevents ion flow across the neural membrane and forces the
current to flow from node to node.
Axon terminals
Small knobs on the end of the axons that contain
neurotransmitter chemicals that are released when a nerve
impulse arrives there.
Neurilemma
Membrane that covers the myelin wrapped around some
axons and dendrites. Has a protective function and can assist
in the regrowth of damaged axons and dendrites.
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