Which of the following electrolytes plays a crucial role in the regulation of muscle contraction and relaxation by acting as a cofactor for the enzyme troponin?
Explanation
Calcium ions play a crucial role in muscle contraction and relaxation by acting as a cofactor for the enzyme troponin, which regulates the interaction between actin and myosin filaments.
Mnemonic
'Calcium' helps 'Catch' muscles
Source
Berne and Levy Physiology