The Sarcomere: The key to muscle function is contraction

The principal functionality of muscle is rooted in its ability to contract and relax. The foundation for muscle contraction is the sarcomere. Sarcomeres contain a motor protein called myosin, which powers the muscle to contract by “grabbing” onto another protein called actin and “flexing.” When the myosin releases the actin, the muscle relaxes. This process is regulated by another protein called troponin.

Learn about the sarcomere Rectangle


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