AP waveform - Chapter 5

Question 1

Rising/Depolarization phase

Answer 1

• membrane is depolarizing rapidly until about 30 or 50 mV
• membrane becomes leakier to sodium, causing an influx of it

Question 2

Peak

Answer 2

• depolarization stops
• single voltage
• top of the waveform

Question 3

Falling/Repolarization phase

Answer 3

• membrane is repolarizing back to resting membrane potential
• voltage gated potassium channels open, allowing for an efflux of potassium

Question 4

Undershoot/hyperpolarization phase

Answer 4

• membrane potential becomes more negative than resting membrane potential
• K channels are leaky, causing an additional efflux of the ion and making the membrane get closer to K’s Nernst potential

Question 5

Overshoot

Answer 5

• area under the curve where the membrane has repolarized
• area under the curve where the membrane has hyperpolarized

Question 6

Label each of the phases

Answer 6