Types of Axons
Axons are of two types
- Myelinated and
- Non-myelinated
In the case of myelinated axons the neurilemma is ensheathed by another covering, the myelin sheath, composed of complex lipoproteins. The terminal branches, dendrites, cell body (perikaryon) and the initial region of the axon (the axon hillock) are devoid of myelin sheath: Although the dendrites are relatively short, unsheathed, tapering, irregular in diameter, and branched in a wide array of patterns, the cell body cytoplasm extends into them. The dendrites receive synaptic endings over much of their surface and thus constitute the receptive surface of the neuron. They are like receiving antennae as a nerve cell receives messages along the dendrites but sends messages along the axon.