Action Potential Quiz

What is the primary ion responsible for depolarization during an action potential?

• Potassium (K⁺)

• Calcium (Ca²⁺)

• Sodium (Na⁺)

• Chloride (Cl⁻)

What happens to the resting membrane potential when a neuron is stimulated to threshold?

• It becomes more negative.

• It becomes less negative.

• It remains unchanged.

• It becomes neutral.

During repolarization, which ion moves out of the cell?

• Potassium (K⁺)

• Sodium (Na⁺)

• Calcium (Ca²⁺)

• Chloride (Cl⁻)

What is the typical resting membrane potential of a neuron?

• +30 mV

• -70 mV

• 0 mV

• -90 mV

Which ion channels open first during an action potential?

• Potassium channels

• Chloride channels

• Sodium channels

• Calcium channels

What term describes the time during which a second action potential cannot be initiated?

• Relative refractory period

• Absolute refractory period

• Resting period

• Repolarization period

The movement of ions during an action potential occurs through:

• Passive diffusion only

• Voltage-gated ion channels

• Endocytosis

• Ligand-gated ion channels

What role does the sodium-potassium pump play after an action potential?

• Initiates depolarization

• Restores resting membrane potential

• Blocks ion movement

• Activates calcium channels

Which of the following contributes to the resting membrane potential?

• Equal ion distribution across the membrane

• Selective permeability of the membrane

• Continuous action potentials

• Neutral charge inside the cell

What triggers voltage-gated sodium channels to open?

• A change in membrane potential

• Binding of a neurotransmitter

• Ion pump activity

• Mechanical stimulation