Question

Hyperkalemia is a condition where extracellular potassium is higher than normal.

A. Hyperkalemia causes the resting membrane potential to be more positive because the driving force on the movement of potassium through leak channels is shifted.
B. Hyperkalemia causes the resting membrane potential to be more negative because the equilibrium potential for potassium is more negative
C. Hyperkalemia Increases the probability that an action potential will be triggered because the Action Potential threshold is more negative
D. Hyperkalemia causes the resting membrane potential to be more negative because more voltage gated potassium channels are open.

Answer 1

Hyperkalemia is an elevated level of extracellular potassium that can cause partial depolarization of cells, affecting the nervous system and heart function. It disrupts the resting membrane potential, which is maintained by ion concentration differences and the sodium-potassium pump.

Step-by-step explanation:

Hyperkalemia is a condition characterized by elevated extracellular potassium levels that can affect various bodily systems, including skeletal muscles, the nervous system, and the heart. Increased dietary intake of potassium can lead to excessive potassium in the extracellular fluid (ECF), resulting in partial depolarization of cells. Such partial depolarization or excitation makes cells less able to repolarize, which particularly impacts cardiac cells by preventing the heart from relaxing after a contraction, potentially leading to fatal outcomes. High levels of potassium in the ECF can also impair nervous system functions, causing symptoms like mental confusion, numbness, and weakened respiratory muscles.

The resting membrane potential is pivotal for normal cell function, especially in neurons and muscle cells. The resting membrane potential is determined by the difference in the concentration of ions, particularly potassium ions (K+), inside and outside the cell. This potential is maintained by the sodium-potassium pump and leakage channels, with the pump moving K+ ions into the cell and Na+ ions out. However, during hyperkalemia, the elevated extracellular K+ concentration can disrupt this balance, altering the membrane potential and impacting cell function and excitability.