What does the all-or-nothing principle mean for a nerve impulse?

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Question

What does the all-or-nothing principle mean for a nerve impulse?

Accepted Answer

An action potential only fires if the threshold is reached, and is always the same size — Award 1 mark. Stimulus intensity is coded by the frequency of impulses, not their size.

Answer

Any stimulus at all will trigger an impulse

Answer

Several impulses always travel together

Answer

A stronger stimulus produces a larger action potential

Answer

An action potential only fires if the threshold is reached, and is always the same size

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