Calcium (Ca) is important for which aspect of physiological function?

Calcium plays a crucial role in regulating heart and muscle function, which is why the answer is C. In the body, calcium ions are essential for the normal functioning of muscles, including the heart. When muscles receive a signal to contract, calcium ions are released, facilitating the interaction between proteins in muscle cells, which leads to contraction. In the heart, calcium is necessary for electrical conduction, helping to maintain a regular heartbeat.

Additionally, calcium is involved in the release of neurotransmitters, which are chemicals that transmit signals in the nervous system, impacting muscle movement and heart function. Without adequate levels of calcium, these processes can be disrupted, leading to arrhythmias or muscle weakness.

Although calcium has various roles in the body, such as contributing to bone health and possibly influencing other physiological functions, its primary significance in this context revolves around its essential contributions to heart and muscle activity.