PHGY 209 Study Guide - Final Guide: Cerebral Cortex, Muscle Atrophy, Baroreceptor

• School: McGill University
• Department: Physiology
• Course: PHGY 209
• Professor: Ann Wechsler

Document Summary

Types of muscles: skeletal muscle: posture, locomotion, voluntary movement (conscious control, cardiac muscle: rhythmic contractions of heart, smooth muscle: involuntary contraction in blood vessels, gut, bronchi and uterus. Composed of bundles of long thin cells call muscle fibers (cellular level) Fibers bundle to form fascicle, and then they bundle to form muscle. Muscle is attached to tendons at each end: contraction of skeletal muscle => pulls on tendon => flexion of joints. Skeletal muscle and muscle fibers are stripped (perpendicular to long axis of muscle) Muscle fibers are generated by fusion of myoblast (precursor cells: multinucleated, more copies of genes (mrna, mrna does not need to be exported at the end of fibre. Muscles fibers: composed of bundle of myofibril. Myofibril: same stripped pattern, lined the one of fibre and muscle. Caused by alternating light i bands (center z-line) and dark a-bands. Z-lines delineate sarcomere: contractile unit of skeletal muscle. H zone: only thick filaments (m line in the middle)