Muscle contraction does not shorten the muscle filaments (myosin and actin). How then, does a contraction produce tension?
What will be an ideal response?
Neither actin nor myosin filaments change length, but their relative positions change. Myosin filaments do not change position but myosin heads bind to actin filaments and slide them toward the center of a sarcomere (the contractile unit of a muscle). As the actin filaments are pulled inward, the ends of the sarcomere are drawn closer together, and the sarcomere shortens. It is the shortening of the sarcomere that creates muscle tension.
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What will be an ideal response?