A 24-year-old soldier sustains a burn injury over 60% of his body surface area, which leads to a decrease in the serum K⁺ concentration from a normal value of 4 mEq/L to 2.5 mEq/L. Which set of changes best describes the resting membrane potential and the K⁺ Nernst potential in a cardiac myocyte after the injury? $\begin{array}{c}\begin{array}{lll} \underline{\text {Resting Membrane Potential}}\\\text {A. \quad Less negative}\\\text {B.\quad Less negative}\\\text {C. \quad More negative}\\\text {D. \quad More negative}\\\text {E.\quad No change} \end{array}\begin{array}{lll} \underline{\text {$\mathrm{K}^{+}$Nernst Potential}}\\ \text {Less negative}\\\text {More negative}\\\text {Less negative}\\\text {More negative}\\\text {No change}\end{array}\end{array}$

Question

A 24-year-old soldier sustains a burn injury over 60% of his body surface area, which leads to a decrease in the serum K⁺ concentration from a normal value of 4 mEq/L to 2.5 mEq/L. Which set of changes best describes the resting membrane potential and the K⁺ Nernst potential in a cardiac myocyte after the injury?

\begin{array}{c}\begin{array}{lll} \underline{\text {Resting Membrane Potential}}\\\text {A. \quad Less negative}\\\text {B.\quad Less negative}\\\text {C. \quad More negative}\\\text {D. \quad More negative}\\\text {E.\quad No change} \end{array}\begin{array}{lll} \underline{\text {\(\mathrm{K}^{+}\)Nernst Potential}}\\ \text {Less negative}\\\text {More negative}\\\text {Less negative}\\\text {More negative}\\\text {No change}\end{array}\end{array}

Quizplus · Accepted Answer

The Answer of A 24-year-old soldier sustains a burn injury over 60% of his body surface area, which leads to a decrease in the serum K⁺ concentration from a normal value of 4 mEq/L to 2.5 mEq/L. Which set of changes best describes the resting membrane potential and the K⁺ Nernst potential in a cardiac myocyte after the injury? $\begin{array}{c} \begin{array}{lll} \underline{\text {Resting Membrane Potential}}\ \text {A. \quad Less negative}\ \text {B.\quad Less negative}\ \text {C. \quad More negative}\ \text {D. \quad More negative}\ \text {E.\quad No change} \end{array} \begin{array}{lll} \underline{\text {$\mathrm{K}^{+}$Nernst Potential}}\ \text {Less negative}\ \text {More negative}\ \text {Less negative}\ \text {More negative}\ \text {No change} \end{array} \end{array}$

A 24-Year-Old Soldier Sustains a Burn Injury Over 60% of His