Which membrane protein transport process plays an important role in terminating the contraction of cardiac muscle? A) Ca ²⁺-ATPase pumps move Ca²⁺ from the T-tubule back into the sarcoplasmic reticulum. B) Na⁺/K⁺-ATPase pumps move Na⁺ back into the cytosol and K⁺ back into the T-tubule lumen. C) Ca²⁺-ATPase pumps move Ca²⁺ from the cytosol back into the sarcoplasmic reticulum. D) Na⁺/Ca²⁺-exchangers move Na⁺ out of the cytosol in exchange for Ca²⁺ movement into the sarcoplasmic reticulum. E) Na⁺/K⁺-ATPase pumps move Na⁺ and K⁺ back out of the cell.

Question

Quizplus · Accepted Answer

Ca ²⁺-ATPase pumps move Ca²⁺ from the cytosol back into the sarcoplasmic reticulum, which reduces the concentration of calcium ions in the cytosol, leading to the termination of the contraction of cardiac muscle.

Which Membrane Protein Transport Process Plays an Important Role in Terminating