Question
The graph shows changes in the membrane potential in an action potential.
What is the approximate value of the threshold potential?
A. −88 mV
B. −70 mV
C. −50 mV
D. +45 mV
▶️Answer/Explanation
Markscheme
C
Question
The image shows a neuron.
What is the function of X?
A. Increases the speed of transmission along the axon
B. Increases the rate of exchange of sodium and potassium ions
C. Holds bundles of neurons together to form a nerve
D. Determines the direction of the action potential
▶️Answer/Explanation
Markscheme
A
Question
How does potassium move across the membrane of a neuron during repolarization?
A. Simple diffusion
B. Facilitated diffusion
C. Endocytosis
D. Active transport
▶️Answer/Explanation
Markscheme
B