Asked by tatiana vayserberg on Jun 24, 2024
Verified
Membrane potential cannot exceed +30 mV because at this level, voltage-gated sodium channels close, and ____.
A) potassium moves across the cell membrane via passive transport proteins
B) sodium moves across the cell membrane via passive transport proteins
C) potassium gated channels open
D) potassium flows into the cytoplasm
E) the action potential is not propagated
Membrane Potential
The voltage difference across a cell's plasma membrane, due to the distribution of ions, important for conduction of impulses in neurons.
Voltage-Gated
Relating to ion channels that open or close in response to changes in membrane potential.
Sodium Channels
Protein channels in cell membranes that allow the passage of sodium ions into and out of the cell, critical for generating and transmitting electrical signals.
- Explain the order and processes involved in an action potential.
Verified Answer
AA
Ashley AttkissonJun 30, 2024
Final Answer :
C
Explanation :
At a membrane potential of +30mV, the depolarization triggers the opening of voltage-gated potassium channels, leading to an efflux of potassium ions, which causes the membrane potential to become more negative. This repolarization event causes the sodium channels to close, stopping the influx of sodium ions. Therefore, the correct answer is C.
Learning Objectives
- Explain the order and processes involved in an action potential.