MUSCLE PHYSIOLOGY

Detailed explanation-1: -A sarcomere is the basic contractile unit of muscle fiber. Each sarcomere is composed of two main protein filaments-actin and myosin-which are the active structures responsible for muscular contraction.

Detailed explanation-2: -The smallest contractile unit of skeletal muscle is the muscle fiber or myofiber, which is a long cylindrical cell that contains many nuclei, mitochondria, and sarcomeres (Figure 1) [58]. Each muscle fiber is surrounded by a thin layer of connective tissue called the endomysium.

Detailed explanation-3: -The smallest contractile unit in striated muscles is the sarcomere.

Detailed explanation-4: -The sarcomere is the smallest functional unit of a skeletal muscle fiber and is a highly organized arrangement of contractile, regulatory, and structural proteins. It is the shortening of these individual sarcomeres that lead to the contraction of individual skeletal muscle fibers (and ultimately the whole muscle).

Detailed explanation-5: -Sarcomeres are the smallest functional contractile unit of muscle, and myofibrils are striated muscle organelles that are comprised of sarcomeres that are strictly aligned in series.