Muscle Physiology

1. Muscle Physiology

2. Types of Muscle • Skeletal • Attached to bones • Makes up 40% of body weight • Responsible for locomotion, facial expressions, posture, respiratory movements, other types of body movement • Voluntary in action; controlled by somatic motor neurons • Smooth • In the walls of hollow organs, blood vessels, eye, glands, uterus, skin • Some functions: propel urine, mix food in digestive tract, dilating/constricting pupils, regulating blood flow, • In some locations, autorhythmic • Controlled involuntarily by endocrine and autonomic nervous systems • Cardiac • Heart: major source of movement of blood • Autorhythmic • Controlled involuntarily by endocrine and autonomic nervous systems

3. Muscle = group of fascicles Muscle fibers extend length of muscle from tendon to tendon 1- Skeletal Muscle Structure

4. Connective Tissue of a Muscle • Epimysium. Dense regular c.t. surrounding entire muscle • Separates muscle from surrounding tissues and organs • Connected to the deep fascia • Perimysium. Collagen and elastic fibers surrounding a group of muscle fibers called a fascicle • Contains b.v and nerves • Endomysium. Loose connective tissue that surrounds individual muscle fibers • Also contains b.v., nerves, and satellite cells (embryonic stem cells function in repair of muscle tissue • Collagen fibers of all 3 layers come together at each end of muscle to form a tendon or aponeurosis.

5. Connective Tissue of a Muscle • Epimysium. Dense regular c.t. surrounding entire muscle • Separates muscle from surrounding tissues and organs

6. Connective Tissue of a Muscle • Perimysium. Collagen and elastic fibers surrounding a group of muscle fibers called a fascicle

7. Connective Tissue of a Muscle • Endomysium. Loose connective tissue that surrounds individual muscle fibers

8. Fig. 10.03

11. Fig. 10.04

13. Fig. 10.06

18. Fig. 10.07