High School

Which of the following statements is true about leak channels and their relationship to the membrane potential?

1) Leak channels allow the movement of ions across the cell membrane.
2) Leak channels are only found in animal cells.
3) Leak channels are responsible for maintaining the resting membrane potential.
4) Leak channels are gated channels that open in response to a stimulus.

Answer :

Final answer:

Leak channels are continuous, non-gated channels that allow potassium ions to move across the cell membrane, maintaining the resting membrane potential. They are distinct from voltage-gated channels, which open due to membrane potential changes, and are found in both animal and plant cells.Corect option 3) Leak channels are responsible for maintaining the resting membrane potential

Explanation:

The leak channels play a pivotal role in maintaining the resting membrane potential of a neuron by allowing a baseline level of ion movement through the neuron's membrane. These channels allow potassium ions (K+) to leak out of the cell due to the concentration gradient when the neuron is at rest. Unlike voltage-gated channels that open in response to a change in the membrane potential, leak channels are not gated and are open continuously, therefore not responding directly to stimuli in the way voltage-gated channels do. It is important to note that leak channels are not exclusive to animal cells; they are also found in plant cells and contribute to the electrochemical gradient necessary for neuron function. Moreover, the resting membrane potential is largely set by the equilibrium potential of potassium, which reflects the activity of non-gated (leak) potassium channels along with the action of the sodium-potassium pump.