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Human Body
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incapable of dividing itself and when a neuron dies, it is not replaced. All neurons in a body were already present at birth. No new ones are added, but a considerable number might be lost.
WHICULO ANIMI
dendrites
axons
presynaptic axon endings
Typical neurons: A. monopolar sensory neuron;
B. busolar sensory neuron: C motor neuron Each neuron conducts impulses in only one direction. The flow is toward the cell body along the dendrites and away from the cell body along the axons. Thus two separate sets of neurons are necessary for the two-way traffic of messages in the peripheral nervous system. Thus a functional classification of neurons yields two main groups viz., (i) sensory or afferent neurons transmit impulses from
1. There is a third group of neurons referred to as inter-Deurons. They
are restricted to the C.N.S, and relay impulses to various functional centres in the brain or spinal cord.
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