Answer: Na+ rushes into the cell.
- A K+ rushes into the cell
- B Na+ rushes into the cell
- C Cl- rushes out
- D K+ rushes out
Correct answer: B. Na+ rushes into the cell
Explanation: During an action potential, Na+ channels open and Na+ rushes into the cell, making the inside more positive (depolarization).
Structure of a neuron. Image: LadyofHats (Mariana Ruiz), Public Domain, via Wikimedia Commons.
Concept context
Brain, spinal cord, neurons, reflex arcs, and sense organs.