Copyright 2003 by Mosby, Inc. All rights reserved. CHAPTER 14 MUSCULAR SYSTEM

Copyright 2003 by Mosby, Inc. All rights reserved. Structure and Function The human body has more than ___ muscles Muscles are the “organs” of the muscular system The functions of the muscular system –Aid in ________________ –Provide and maintain posture –Protect internal organs –Provide movement of blood, food, and waste products through the body –Open and close body ________ –Produce heat

Copyright 2003 by Mosby, Inc. All rights reserved. Names of Muscles Muscles are named for: –___________ (adductor longus- adducts thigh) –Direction of fibers and shape (deltoid) –Point of attachment (___________radialis) –Size (gluteus maximus) –Number of __________ (bicep brachii) –Combo (pectoralis major: pect=shoulder, major=big)

Copyright 2003 by Mosby, Inc. All rights reserved. Table 14-1 Types of Muscle Tissue

Copyright 2003 by Mosby, Inc. All rights reserved. Muscle Cells

Copyright 2003 by Mosby, Inc. All rights reserved. Skeletal Muscle (voluntary) Makes up more than ____% of a person’s body weight Looks striated, or banded, under the microscope; dense connective tissue Skeletal muscles have three parts –___________ is one end of the muscle, attached to the less movable part of the bone –Insertion is the other end of the muscle, attached to the more movable part of the bone –The action, or __________, is the thick middle part of the muscle

Copyright 2003 by Mosby, Inc. All rights reserved. Figure 14-5 Basic Types of Muscle Movement

Copyright 2003 by Mosby, Inc. All rights reserved. Visceral Muscle (smooth) Lines various _____________ organs Makes up the walls of blood vessels Found in the tubes of the digestive system Smooth and has no striations; longitudinally and circularly arranged Controlled by the autonomic nervous system

Copyright 2003 by Mosby, Inc. All rights reserved. Cardiac Muscle (involuntary) ______cardial (heart muscle) Found only in the heart Striated muscle; figure 8 packaging of cells/banded Under involuntary control Has specialized cells that provide a _________________ for contraction Coordinated to act as a pump

Copyright 2003 by Mosby, Inc. All rights reserved. Muscle Contraction _____________ contraction is muscle shortening that produces movement Muscle tone or tonus is a state of partial contraction that maintains a person’s posture Once a muscle is stimulated to contract; it will contract to its’ fullest ____________ Isometric contraction does not cause muscle shortening or movement A twitch is a quick, jerky contraction of a whole muscle from one stimulus ____________ causes decreased muscle strength due to connective tissue replacing some muscle fibers

Copyright 2003 by Mosby, Inc. All rights reserved. Muscle Contraction (continued) ___________ contraction is more sustained than a twitch and is caused by many stimuli in rapid succession Fibrillation is uncoordinated contraction of muscle fibers Convulsions are contractions of groups of muscles in an abnormal manner ___________ are involuntary, sudden, and prolonged contractions Build up of lactic acid causes muscle fatigue and muscle soreness

Copyright 2003 by Mosby, Inc. All rights reserved. Figure 14-8 Sliding Filament Theory

Copyright 2003 by Mosby, Inc. All rights reserved. Assessment Techniques ____________ tests Joint motion measured using a protractor ____________ tests Electromyography tests Muscle biopsy

Copyright 2003 by Mosby, Inc. All rights reserved. Disorders of the Muscular System Back pain –From weakened muscles around the spine in the lower back __________________ (shortening of muscle) –A condition in which muscles remain contracted as a joint loses flexibility and ligaments and tendons shorten and causes atrophy Muscle cramp –A sudden involuntary ______________ of a muscle producing pain

Copyright 2003 by Mosby, Inc. All rights reserved. Disorders of the Muscular System (continued) Muscular ________________ –A group of genetic diseases involving painless, gradual atrophy of muscle tissue Fibromyalgia –A group of muscle disorders affecting the tendons, ligaments, and other fibrous tissues Gangrene –Caused by Clostridium bacteria that _______ muscle tissue

Copyright 2003 by Mosby, Inc. All rights reserved. Disorders of the Muscular System (continued) _____________ –The abnormal protrusion of a body part into another body area Myasthenia gravis –A condition in which nerve impulses _____ ________ transmitted normally from the brain to the muscles Poliomyelitis –A viral infection that results in paralysis of muscles

Copyright 2003 by Mosby, Inc. All rights reserved. Disorders of the Muscular System (continued) Muscle __________ –A traumatic injury to the ligaments of a joint; small microfiber tears (grade 1, 2 or 3) Muscle __________ –Torn or stretched tendons and muscles, causing pain Pes planus –Called “flatfoot” or “fallen arches,” may be congenital or result from weakened foot muscles

Copyright 2003 by Mosby, Inc. All rights reserved. Disorders of the Muscular System (continued) __________myalgia- pain in many muscles Tetanus –Commonly called “_________,” is caused by a bacterial infection Trichinosis –A parasitic infection caused by eating undercooked pork

Copyright 2003 by Mosby, Inc. All rights reserved. Issues and Innovations Sports medicine – Treating sports injuries – Directing healthful development and training of athletes – Biomechanics Fitness fad – Importance of regular exercise for good health – Exercise obsession