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Bipolar neurons

• They are fusiform or spindle-shaped. Each cell has two processes, a single
axon arises from one pole of the cell and a single dendrite arises from the
opposite pole. (e.g., receptor neurons for the senses of smell sight and
balance).

Multipolar neurons

• They are the most common forms. Each cell has a single axon and numerous
dendrites. Dendrites may all arise from one pole of the cell body or may extend
from all parts of the cell body. (e.g., neurons of CNS and autonomic ganglia).

According to their shapes, three types of multipolar neurons are recognized:
Polygonal (stellate neurons): are irregulars in shape with dendrites arising from
different body regions (e.g., autonomic ganglia).
Pyramidal neurons: are pyramidal in shape with dendrites arising from the apex and
axon arises from its base (e.g., cerebral cortex).
Pyriform neurons: are large, flask-shaped with extensively branched apical dendrites
(e.g., Purkinje cells of the cerebellum).
According to the length of their axons, two types are recognized:
Golgi types I neurons: have long axons extend through peripheral nerves to reach
their effector organs.
Golgi types II neurons: have short axons usually end in the immediate vicinity of the
cell.

Synapses

• They are sites at which nerve impulses are either chemically or electrically
transmitted from one neuron to another.

• Classification of synapses
According to the places at which the telodendritic process synapses on the
postsynaptic neuron:

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