What could lead to hyperpolarization of the cell membrane?

What could lead to hyperpolarization of the cell membrane?

• A. An acetylcholine-gated ion channel opened on the cell membrane to allow influx of Na+ ions
• B. An acetylcholine-gated ion channel opened on the cell membrane to allow influx of Cl- ions
• C. A glycine-gated ion channel opened on the cell membrane to allow influx of Na+ ions
• D. A glycine-gated ion channel opened on the cell membrane to allow influx of Cl- ions

Answer: (D)

Hyperpolarization of the cell membrane occurs when the inside of the cell becomes more negatively charged than its resting potential, making it less likely to generate an action potential. This can happen when negatively charged ions flow into the cell or positively charged ions flow out. In the case of a glycine-gated ion channel, when it opens and allows the influx of chloride ions (Cl-), the internal environment of the cell becomes more negative. This increase in negative charge inside the cell leads to hyperpolarization. Glycine is a neurotransmitter that typically has an inhibitory effect, and the opening of its receptor channels allows Cl- to enter, which reinforces the negative potential inside the cell, thus contributing to hyperpolarization. The other options primarily involve sodium ions entering the cell, which would generally result in depolarization and making the cell more likely to fire an action potential, rather than hyperpolarization. This contrasting effect helps to clarify why the influx of chloride ions through the glycine-gated channel is responsible for hyperpolarization.

Hyperpolarization of the cell membrane occurs when the inside of the cell becomes more negatively charged than its resting potential, making it less likely to generate an action potential. This can happen when negatively charged ions flow into the cell or positively charged ions flow out.

In the case of a glycine-gated ion channel, when it opens and allows the influx of chloride ions (Cl-), the internal environment of the cell becomes more negative. This increase in negative charge inside the cell leads to hyperpolarization. Glycine is a neurotransmitter that typically has an inhibitory effect, and the opening of its receptor channels allows Cl- to enter, which reinforces the negative potential inside the cell, thus contributing to hyperpolarization.

The other options primarily involve sodium ions entering the cell, which would generally result in depolarization and making the cell more likely to fire an action potential, rather than hyperpolarization. This contrasting effect helps to clarify why the influx of chloride ions through the glycine-gated channel is responsible for hyperpolarization.