Page 85 - Headlines Histology2024_Neat

• They are the major sites of information input into the neurons.
• The main dendritic branch contains Nissl granules, mitochondria, microtubules

and neurofilaments. These organelles become progressively scantier toward the
ends of the dendrites. Synaptic vesicles are absent.

Mention the differences between axon and dendrites?

Criteria Axon Dendrites

Contour Regular contour Irregular
and uniform diameter contour with broad
base and tapered ends

Number Single Multiple

Branching Less branched, Highly branched
only few collateral
branches

Nissl bodies Absent Present

Myelin sheath Present Absent

Function Transmit nerve Transmit nerve
impulses away from the impulses toward the
cell body cell body

CLASSIFICATION OF NEURONS
According to the number of their processes

Unipolar (Pseudounipolar) neurons

• They are flask-shaped with a single large process that divides into two main
branches; one of them acts as axon and the other acts as dendrites. (e.g.,
sensory neurons in craniospinal ganglia).

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