🧠 "Nerve Spark: Action Potential Quiz" ⚡

What is the resting membrane potential of a typical neuron?

• +70 mV

• -70 mV

• 0 mV

• -30 mV

Which ion is primarily responsible for the depolarization phase of an action potential?

• Potassium (K⁺)

• Calcium (Ca²⁺)

• Sodium (Na⁺)

• Chloride (Cl⁻)

What term describes the minimum stimulus required to generate an action potential?

• Limit stimulus

• Threshold stimulus

• Peak potential

• Submaximal stimulus

During repolarization, which ion moves out of the neuron?

• Na⁺

• Ca²⁺

• Cl⁻

• K⁺

What happens if the membrane potential becomes more negative than the resting potential?

• Depolarization

• Hyperpolarization

• Repolarization

• Excitation

Which of the following best describes the "all-or-none" law of action potentials?

• Weak stimuli cause weak responses.

• Larger stimuli produce larger action potentials.

• Once threshold is crossed, an action potential always occurs.

• Action potential size depends on ion concentration.

What ensures that a second action potential cannot be generated immediately after the first one?

• Low Neuron battery

• Refractory period

• Continuous conduction

• Ion channels get bored

Which of the following speeds up nerve conduction?

• Unmyelinated axons

• Thin axons

• Continuous conduction

• Saltatory conduction

At rest, which ion is in higher concentration inside the neuron?

• Na⁺

• K⁺

• Ca²⁺

• Cl⁻

What causes the membrane potential to return to negative after depolarization?

• Na⁺ exits the cell

• K⁺ enters the cell

• K⁺ exits the cell

• Na⁺ enters the cell