Neurons

Neuron

Basic building blocks of the nervous system.

Nerve cells that process and transmit messages through electrical and chemical signals

Sensory neurons

Carry messages from the PNS to the CNS.

Long dendrites and short axons

Relay neuron

Connect the sensory neurons to motor or other relay neurons.

Short dendrites and short axons

Motor neurons

Connect the CNS to effectors like muscles and glands

Short dendrites and long axons

Dendrites

Branch-like structures.

Receive information from other neurons

Sends nerve impulses towards cell body

Cell body

Includes a nucleus which contains the genetic material

Axon

Carries nerve impulses away from the cell body

Myelin sheath

Insulates and protects the axon

Helps to speed up electrical transmission along the axon

Schwann cells

Maintains the myelin sheath

Nodes of Ranvier

Gaps in the myelin sheath.

Forces the impulse to ‘jump’ across the gaps along the axon

Helps to increase the speed of the electrical impulse

Terminal boutons

Sends impulses to the next neuron across the synapse through the release of neurotransmitters