ANP 1105 Chapter Notes -Muscle Contraction, Creatine Kinase, Motor Neuron

• School: University of Ottawa
• Department: Anatomy and Physiology
• Course: ANP 1105
• Professor: Joanne Savory

Document Summary

Pacemaker sets rate of contraction; neural input can increase rate: skeletal muscle, smooth muscle. Muscle functions: generate movement, maintain posture, joint stabilization, generation of heat: maintenance of body temperature; esp: skeletal muscle. Functional characteristics of muscle: excitability (irritability): ability to receive and respond to a stimulus . Stimulus: usually a chemical (nt, hormone, ph) Response = ap along sarcolemma + muscle contraction: contractility: ability to shorten forcibly when adequately stimulated , extensibility: ability to be stretched or extended from rest , elasticity: ability to resume resting length after being stretched . Long, cylindrical cell with many oval nuclei (cell membrane is the sarcolemma: huge cell (diameters of 10-100 micrometers and lengths in cm) Sacroplasm contains lots of glycogen & myoglobin lots of myofibrils, extensive sarcoplasmic reticulum (fluid filled membrane bound chambers storing calcium); t- tubules (not intracellular, brings action potential deep within the sarcoplasmic reticulum and myofibrils) Myofibrils: each muscle fiber (cell) consists of parallel myofibrils.