Speed Of The Nerve Impulse

Question 0

What cannot be generated during the refractory period?

Answer 0

A further action potential

Question 1

Name three factors that affect the speed at which an action potential travels?

Answer 1

The myelin sheath, the diameter of the axon and the temperature

Question 2

Once an action potential has happened, what prevents the inward movement of sodium ions?

Answer 2

The voltage-gated channels are closed

Question 3

What are the three purposes that the refractory period serves?

Answer 3

It ensures that an action potential is propagated in one direction only, It produces discrete impulses and it limits the number of action potentials

Question 4

What are nerve impulses described as?

Answer 4

All-or-nothing responses

Question 5

What is the certain level of stimulus which triggers an action potential called?

Answer 5

The threshold value

Question 6

What happens if the strength of the stimulus is below the threshold value?

Answer 6

An action potential will not be generated

Question 7

What are the two ways in which an organism can perceive the size of the stimulus?

Answer 7

By the number of impulses passing in a given time and by having different neurones with different threshold values