During Muscular Contraction,cross-Bridges Form Between _____ and _____

Question

During muscular contraction,cross-bridges form between _____ and _____ .
A)actin,myosin
B)actin,tropomyosin
C)myosin,troponin
D)myosin,tropomyosin
E)troponin,calmodulin

Accepted Answer

During muscular contraction, cross-bridges form between the actin and myosin filaments. The myosin heads bind to the actin filaments and cause a sliding movement, resulting in muscle contraction. Troponin and tropomyosin are regulatory proteins that are involved in controlling the interaction between actin and myosin, but they do not directly form cross-bridges. Calmodulin is a calcium-binding protein involved in muscle relaxation, but it is not directly involved in muscle contraction.