nerve impulse

Question 1

what is resting potential

Answer 1

the potential difference across the neurone membrane when no action potential is being initiated

Question 2

resting potential

Answer 2

no impulse is being sent so the membrane is polarised, - 70mV inside the axon and + 40mV outside

Question 3

action potential

Answer 3

membrane becomes depolarised and the chargers switch, sodium gates open so Na+ move into the cell

Question 4

after action potential resting

Answer 4

membrane is repolarised and charges are back to normal, potassium gates open so K+ diffuse out and Na+/K+ pump is needed to restore ions to correct location

Question 5

what is a refractory period

Answer 5

• a gap between impulses where the membrane cant take another action potential until the Na+ and pumped out and K+ pumped in
• good for the heart muscle
• allows for prolonged muscle contraction