axon hillock

biology

Also known as: initial segment

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June 18, 2026

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The axon hillock is the region of a neuron's cell body where the axon originates. This is a critical area where nerve impulses are generated and then conducted away from the cell body towards other neurons or target cells. The axon itself is a nerve fiber that transmits these impulses, and in vertebrates, it is often covered by a myelin sheath that speeds up transmission. The axon hillock acts as a crucial junction, integrating signals before they are sent down the axon.12

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nervous system
Axon
…at a region called the axon hillock, or initial segment. This is the region where the plasma membrane generates nerve impulses; the axon conducts these impulses away from the soma or dendrites toward other neurons. Large axons acquire an insulating myelin sheath and are known as myelinated, or medullated, fibres.…
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…at a region called the axon hillock, or initial segment. This is the region where the plasma membrane generates nerve impulses; the axon conducts these impulses away from the soma or dendrites toward other neurons. Large axons acquire an insulating myelin sheath and are known as myelinated, or medullated, fibres.…
Read More