The concentration of potassium ions in the solution surrounding an axon was increased and the resting potential recorded each time. The results are shown in Table 4.
| External potassium ion concentration / mmol dm-3 | Resting potential / mV |
|---|---|
| 5 | −70 |
| 10 | −60 |
| 20 | −50 |
| 40 | −35 |
Using Table 4, describe the effect of increasing the external potassium ion concentration on the resting potential.
[1]
Explain the effect shown in Table 4.
[3]
Suggest how a very high potassium ion concentration in the blood could affect the transmission of nerve impulses.
[2]