Voltage-gated Sodium & Potassium Channels (FINAL)

Question 1

How are sodium and potassium channels affected by voltage?

Answer 1

They open or close depending on the voltage across the electrical membrane

Question 2

What is the charge inside the cell during the resting state compared to the outside? Are the ion channels open?

Answer 2

Inside is more negative than outside; channels are closed

Question 3

What happens during depolarization (rising phase)?

Answer 3

Sodium channel opens, pushing sodium inside to make the cell interior more positive

Question 4

What happens during repolarization (falling phase)?

Answer 4

Sodium channels close, and potassium channels open. The outflow of potassium causes the inside to become negative again