(Bio) Quick ActionPotential/membrane potential Question

[yestomeds]

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A condition causes more K+ to be outside of the cell (higher extra-cellular concentration of K+)
This would lead to:
a) more positive resting memb potential. Yep.
b) an easier time generating an action potential (as you're not going from -70mV anymore, you're going from maybe -60 or -52). Yep.
c) decreased membrane threshold. DO NOT GET THIS ONE. The answers booklet explains the above 2 points very well but I don't get the point made by these 3 words, "decreased. membrane. threshold."

Hey so this is from the old EK, passage 404, question 350. (The answers are on p.224)
Please help. (Especially if you yourself have read the q/answer). 🙂

 

[Quinoline]

How does more K+ outside the cell cause a more positive resting membrane potential and not more negative?

 

[goodtime]

c and b literally mean the same thing. A decreased membrane threshold means it is easier to reach an action potential. Threshold is defined as the required potential to reach depolarization. It simply means it is easier to reach depolarization.