Action Potential

Which characteristic defines excitable cells?

• They only respond to chemical signals.

• They can generate an electrical signal from a stimulus.

• They are primarily involved in hormone production.

• They are responsible for storing genetic information.

What is the primary function of the sodium-potassium pump in maintaining cellular balance?

• It moves sodium and potassium ions along their concentration gradients.

• It actively transports sodium ions out of the cell and potassium ions into the cell.

• It generates ATP for cellular energy.

• It facilitates the passive diffusion of ions across the membrane.

What is the typical electrical state of a neuron at its resting membrane potential?

• The inside of the cell is positively charged compared to the outside.

• The inside of the cell is negatively charged compared to the outside.

• There is no electrical charge difference across the membrane.

• The electrical charge rapidly fluctuates between positive and negative.

What event occurs when a neuron's membrane potential reaches the threshold level during an action potential?

• The cell becomes hyperpolarized.

• Gated sodium channels close, preventing ion movement.

• An action potential is triggered, leading to rapid depolarization.

• The cell immediately returns to its resting potential.