Question

Action potential is amplified everywhere EXCEPT:

a. axon hillock

b. nodes of ranvier

c. internal space (space between nodes of ranvier)

Answer 1

Action potential is the change in the electrical potential and which occurs on the surface of cell. Action potential is a short term change. Action potential occurs due to stimulation. And this leads to transmission of electric impulse. This impulse travels across the cell membrane. It involves a series of electrical and chemical changes.

An example of action potential is the nerve impulse passing from nerve fibers to muscles.

Axon hillock is the specialized part of cell which connects to the axon. It is part of axon of a nerve. It connects the cell body with axon. Plasma membrane generates nerve impulse in the axon hillock.

Nodes of ranvier is also called myelin sheath gap. It is seen in the myelinated axon of a nerve. Nodes of ranvier facilitate rapid conduction of nerve impulse.

The internal space ( space between nodes of ranvier) is called internode.

The action potential is amplified everywhere except internal space (space between nodes of ranvier), ie; at the internode. Action potential jump from one node of ranvier to the other node of ranvier. Action potential will not be amplified at the internodes.