Kinesiology 2241A/B Lecture Notes - Lecture 6: Brachialis Muscle, Myocyte, Myofibril

• School: Western University
• Department: Kinesiology
• Course: Kinesiology 2241A/B
• Professor: Thomas Richard Jenkyn

Document Summary

The muscles overlay the skeleton and provide the means to move it. Each muscle produces a motion when it creates tension and tries to shorten. Its attachments and orientation determine what moves and how. Note the different shapes and wrappings of the muscles. Note the different alignment of the fibers within the muscles. Note the size (large or small) of the tendon attachments at either end. The proximal attachment of a muscle is its origin. The distal attachment of a muscle is its insertion. Muscles often have wrapping points or retinacula for redirecting muscle pull between the origin and insertion. Muscles attached to bone via tendon or apneuroses" (wide bands of connective tissue) Each muscle is a coil on a coil on a coil. The smallest contractile unit of muscle is sarcomere. Hundreds of sarcomere connect in long chain (in parallel) to form a myofibril. Several myofibrils (3 to 1000) form each muscle cell (muscle fiber)