Question

Based upon the changes in permeability seen in the trace below and your knowledge of ion distributions across a cell, predict how ion movements would change during an action potential. Drag and drop each phrase into the appropriate box on the action potential trace.

Answer 1

1. Sodium ions move into the system.

2. Sodium ions stop moving into the system.

3. Potassium ions move out of the system.

4. Potassium ions move into system.

Step-by-step explanation:

The picture given is a picture of the neuron polarization and depolarization.

In the 1st phase of the graph, the graph seems to peak up to high values of electric potential differences which is because as the impulse is received by the system the sodium channels of the axon open. This leads to free flow of sodium inside the axon. This depolarises the axon membrane.

As the peak potential of 30mV is met, the sodium channels close. And the potassium channels open up. This leads to the exit of potassium channels out of the axon and the potential drops. This phase is called repolarisation.

The potassium channels are slow channels and they don't close even when the base potential is met. So hyper polarization occur. And finally the potassium channels close and the sodium potassium ATPase starts working bringing potassium inside the axon and sodium outside the axon.