Which describes the response of the voltage-gated channels when an axon is stimulated to threshold? A) K⁺ channels open before the Na⁺ channels. B) Na⁺ channels are activated and then inactivated. C) K⁺ channels open at the same time as the Na⁺ channels. D) K⁺ channels are opened when Na⁺ binds to the channel. E) K⁺ influx causes Na⁺ channels to inactivate.

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When an axon is stimulated to threshold, the voltage-gated Na+ channels (represented by Na⁺) are activated and allow an influx of Na+ ions, leading to depolarization. However, they quickly become inactivated, which allows for the voltage-gated K+ channels (represented by K⁺) to open and allow an efflux of K+ ions, leading to repolarization. This sequence of events is what enables the action potential to propagate down the axon.

Which Describes the Response of the Voltage-Gated Channels When an Axon