Which mineral is involved in both calcium metabolism and muscle contraction?

The mineral that is involved in both calcium metabolism and muscle contraction is indeed calcium. Calcium plays a critical role in the functioning of muscles, as it is essential for the contraction process. When a muscle is stimulated to contract, calcium ions are released from the sarcoplasmic reticulum inside the muscle cells. These ions interact with proteins in the muscle fibers, allowing them to move and produce contraction.

In addition to its direct role in muscle contraction, calcium is also vital for calcium metabolism, which refers to the processes that regulate calcium levels in the body. This involves various physiological functions, including bone formation, blood clotting, and nerve transmission. Calcium's ability to regulate its own levels through a complex interplay with hormones such as parathyroid hormone and calcitonin further emphasizes its significance in overall metabolism and health.

Other minerals like potassium, sodium, and magnesium each play important roles in human physiology, including nerve function, fluid balance, and muscle function, but they do not directly engage in both calcium metabolism and muscle contraction to the extent that calcium does. Thus, calcium stands out as the primary mineral that encompasses both of these crucial functions in the body.