Membrane Potential Quiz

What is the typical value of the resting membrane potential of a neuron?

• +30 mV

• -70 mV

• 0 mV

• +60 mV

Which ion has the highest concentration inside the cell at rest?

• Na+

• K+

• Ca2+

• Cl-

What is the main function of the sodium-potassium pump?

• To depolarize the membrane

• To hyperpolarize the membrane

• To maintain the resting membrane potential

• To initiate action potentials

During an action potential, what causes depolarization?

• K+ ions flowing out of the cell

• Na+ ions flowing into the cell

• Cl- ions flowing into the cell

• Ca2+ ions flowing out of the cell

What is the threshold potential typically around?

• -55 mV

• -70 mV

• 0 mV

• +30 mV

Which of the following best describes repolarization?

• The membrane potential moves toward 0 mV

• The membrane potential returns to the resting level after depolarization

• The membrane potential becomes more negative than the resting level

• The membrane potential becomes more positive than the resting level

What is hyperpolarization?

• The membrane potential becomes more positive than the resting level

• The membrane potential becomes less negative than the resting level

• The membrane potential becomes more negative than the resting level

• The membrane potential returns to the resting level after depolarization

Which type of ion channel opens in response to a change in membrane potential?

• Ligand-gated channels

• Mechanically gated channels

• Voltage-gated channels

• Temperature-gated channels

What is the role of potassium channels during the repolarization phase of an action potential?

• They open to allow K+ ions to flow out of the cell

• They open to allow K+ ions to flow into the cell

• They close to stop K+ ions from flowing out of the cell

• They close to stop K+ ions from flowing into the cell

What triggers the opening of voltage-gated sodium channels at the start of an action potential?

• The membrane potential reaching the threshold potential

• The membrane potential reaching 0 mV

• The membrane potential reaching +30 mV

• The membrane potential returning to the resting level