NATS 1650 Lecture Notes - Lecture 4: Cardiac Muscle, Skeletal Muscle, Myocyte

• School: York University
• Department: Natural Science
• Course: NATS 1650
• Professor: Dr. Nicolette Richardson

Document Summary

Types of muscle tissue: smooth muscle-internal organs, cardiac muscle-heart, skeletal muscle-leg. Muscle fiber= a muscle cell (skeletal or smooth) Cardiac muscle cells aren"t elongated, so are usually just called cardiac muscle sells . Muscle functions: producing movement, maintaining posture and body position, additional functions such as protects organs, regulates passage of substances, and constriction/dilation (eye, blood vessels), generating heat, stabilizing joints. Skeletal muscle: consciously controlled, rich blood supply, each fiber is supplied with a nerve ending (cannot contact without nervous stimulation) Motor unit: a single nerve (neuron) and all of the muscle fibers it innervates (supplies) Thin (action) filament, z disc, h zone, z disc. Sarcomere: thick (myosin) filament, i band, a band, i band, m line. Thin (action) filament, elastic (titin) filament, thick (myosin) filament. Elongated, spindle-shaped fibers (cells); much smaller than skeletal muscle fibers. Located in walls of body organs (except hearts) & blood vessels.