QuestionSBA
QuestionChoice
This is the resting membrane potential of normal cells. It is also maintained via potassium-sodium pumps, potassium leak channels, negatively charged membrane proteins and voltage-gated ion channels.
10003467
b
-60 mV
QuestionChoice
A cardiac myocyte maintains a resting membrane potential of –80 mV. This is achieved through potassium-sodium pumps, potassium leak channels, negatively charged membrane proteins and voltage-gated ion channels. All of these work together to maintain a greater number of cations outside the plasma membrane compared to inside.
10003466
a
-80 mV
QuestionChoice
A membrane potential of +300 mV is extremely high and is unlikely to be found in cells.
10003470
e
+300 mV
QuestionChoice
A membrane potential of +30 mV is the typical threshold potential for an action potential to be fired. This threshold is reached via the opening of sodium (and calcium) ion channels and the closure of potassium channels. This causes an increase in cations inside the cell, and thus a positive charge.
10003469
d
+30 mV
QuestionChoice
A membrane potential of –120 mV would indicate hyperpolarization of a cell. This typically occurs when there is an excess loss of cations from a cell, and it prevents an action potential from being generated.
10003468
c
-120 mV
Concept
Chapter
2693
4169
Resting membrane potential
Topic
206
Physiology
13240
What is the normal resting membrane potential of a cardiac myocyte?
a