V. Anatomy and Innervation of Skeletal Muscle Tissue

A. Nerve and Blood Supply 1. Nerves, containing motor neurons, convey impulses for muscle contraction 2. Contractions burn high degrees of ATP a. To make more ATP, oxygen is needed and supplied by blood b. Each fiber is contacted by a capillary

B. Connective tissue Components 1. The term fascia is applied to a sheet or broad band of fibrous connective tissue underneath the skin or around muscles and organs a. Superficial- under skin b. Deep- around muscles and organs

2. Three layers extend from deep fascia to protect and strengthen skeletal muscle a. epimysium- outer layer encircling the whole muscle b. Perimysium- surround bundles of fibers c. Endomysium- separate each muscle fiber 3. Tendons and aponeuroses are extensions that attach muscle to bone or other tissue

a. Aponeuroses are broad flat tendons that tie into the covering on bone b. Tendon sheaths enclose tendons and allow them to slide back and forth more easily c. Tenosynovitis is an inflammation of tendon sheaths and synovial membranes

C. Motor unit 1. A motor neuron and muscle fibers it stimulates form a motor unit 2. A motor unit may innervate as few as 10 or as many as 2000 muscle fibers, with an average of about 150 per unit