Question

Ca²⁺ ion concentrations are usually lower inside the SR than they are in the rest of the muscle cell.

a. False
b. True

Answer 1

Ca²⁺ ion concentrations are usually lower inside the SR than they are in the rest of the muscle cell.

Step-by-step explanation:

The correct answer is b. True.

Ca2+ ion concentrations are indeed lower inside the sarcoplasmic reticulum (SR) than they are in the rest of the muscle cell. The SR acts as a storage site for Ca2+ ions, which are released during muscle contraction. When the muscle is at rest, Ca2+ ions are actively transported into the SR, resulting in a lower concentration of Ca2+ ions inside the SR compared to the rest of the muscle cell.