Cellular Electricity

Question 1

Based on the information in the above graph, the passive movement of sodium ions through an ion channel down their chemical gradient will be:

Answer 1

into the cell, decreasing membrane potential

Question 2

Action potentials follow the all-or-none principle. This means that:

Answer 2

to get a stronger signal a larger action potential is required

Question 3

If the membrane potential of a cell becomes less negative than its normal resting potential, the cell:

Answer 3

depolarises and the membrane potential difference decreases

Question 4

In the above graph of an action potential, the depolarising phase is dependent on the influx of:

Answer 4

sodium ions

Question 5

Which of these would cause a resting cell to become hyper-polarised?

Answer 5

Closing voltage-gated Na+ channels