Smooth muscle tone is maintained by the prolonged presence of _____ in the muscle cell's cytosol?
A)ATP
B)calcium ions
C)phosphate ions
D)myoglobin
E)None of these choices.

Question

Quizplus · Accepted Answer

Calcium ions play a crucial role in smooth muscle contraction and maintaining smooth muscle tone. In the absence of calcium ions, smooth muscle cells cannot contract, and thus their tone is maintained by the prolonged presence of calcium ions in the cytosol. ATP and phosphate ions are important for energy production but not specifically for smooth muscle tone. Myoglobin is a protein that stores oxygen in muscle cells but does not play a role in maintaining muscle tone.

Smooth Muscle Tone Is Maintained by the Prolonged Presence of _____