Action potential Flashcards
Neuroscience
What is an action potential?
A rapid electrical signal that moves along a neuron due to ion movement across its membrane.
What happens during resting potential?
The neuron is inactive, the inside is negative (-70mV), maintained by the sodium-potassium pump.
What is depolarization?
Na⁺ channels open, Na⁺ rushes in, and the inside of the neuron becomes positive (+40mV).
What is repolarization?
Na⁺ channels close, K⁺ channels open, K⁺ exits, and the neuron restores negativity.
What is hyperpolarization?
Too much K⁺ leaves, making the neuron extra negative, preventing immediate firing.
How does the neuron return to resting potential?
The sodium-potassium pump restores the ion balance and brings the neuron back to -70mV.
What is the sodium-potassium pump?
A membrane protein that uses ATP to pump 3 Na⁺ out and 2 K⁺ in, maintaining resting potential.
