BIO 201 Lecture Notes - Lecture 2: Tensor Fasciae Latae Muscle, Toe, Zygomaticus Major Muscle
Document Summary
Muscle tissue intro: characteristics: contractile, receives stimulation from nervous system and/or endocrine system, functions: facilitates movement or skeleton or organ walls, primary germ layer: mesoderm, muscle exhibits properties of excitability and contractility. Three types of muscle: skeletal: striated due to arrangement of contractile proteins; voluntary; 700 muscles form the muscular system of the body, cardiac: striated; but involuntary, smooth: lacks striations; involuntary. Functions of skeletal muscle tissue: body movement, maintenance of posture- antigravity muscles, storage. Cardiac muscle: found within heart wall, striated, involuntary, have sarcomeres- similar shortening method, autorhythmic- no nerve innervation, does not need a nerve signal to contract. Smooth muscle: found in wall of viscera and blood vessels, single fusiform cells (fatter in the middle, do contract (in units) and create peristaltic contractions, contains actin and myosin but not orderly (no banding or striations, no sarcomeres. Actions of skeletal muscles: agonist- muscle that produces a specific movement, ex.
