HP 2306 Lecture Notes - Lecture 8: Skeletal Muscle, Myocyte, Myosatellite Cell

• School: Baylor University
• Department: Human Performance
• Course: HP 2306
• Professor: Shearer

Document Summary

8 skeletal muscle : structure & function. Human body contains over 600 skeletal muscles: 40-50% of total body weight. Functions of skeletal muscle: force production for locomotion and breathing, force production for postural support (antigravity muscles, heat production during cold stress. Muscle actions: flexors : decrease joint angle, extensors : increase joint angles. Perimysium: surrounds bundles of muscle fibers (fascicles), covering of muscle bundles, fascicles : bundles of muscle fibers. Endomysium: surrounds and covers individual muscle fibers, separates individual muscle fibers. Just below endomysium: satellite cells : found between the endomysium and the sarcolemma, specialized cells found only in skeletal muscle tissue. Myonuclear domain: myonuclear domain is the volume of cytoplasm surrounding each nucleus, each nucleus can support a limited myonuclear domain. More nuclei allow for greater protein synthesis. Important for muscle growth in response to strength and resistance training. Sarcomere : region from a z-line to a different z-line, a structural and functional part of a muscle fiber.