In most excitable cells, the rising phase of the action potential is due to
A)calcium efflux
B)potassium efflux
C)chloride influx
D)potassium influx
E)sodium influx

Question

Quizplus · Accepted Answer

The rising phase of the action potential is due to sodium influx, where sodium ions move into the cell through voltage-gated sodium channels. This causes depolarization of the membrane potential, leading to the initiation of the action potential. Choices A, B, C, and D are incorrect as they describe processes that occur during repolarization or hyperpolarization phases of the action potential, rather than the rising phase.

In Most Excitable Cells, the Rising Phase of the Action