Transcript Muscular System

Tracie Haan
M.E. Meyerhofer
Chelsea Friesen
Muscular System
Muscular System
Physiology
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4 main functions of the muscles:
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Produces movement

Maintain posture
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Reinforces and stabilizes joints
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Generates heat
Muscle Types
 There
are three main
muscle types:
Skeletal
 Cardiac
 Smooth
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Skeletal Muscles
The four primary functions of skeletal muscles:
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 Movement
 Posture
 Support
 Heat regulation
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Controlled under somatic nervous system
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Voluntarily Controlled
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Striated
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Most skeletal muscles are attached to bones

by bundles of collagen fibers known as tendons.
Skeletal Muscle Structure
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Skeletal Muscle Cells (myocytes)
 myoblasts
○ Myofibrils
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Skeletal Muscles
 Belly
○ Fascia:
 Epimysium
 Perimysium
 Endomysium
○ Muscle Fiber (Cell)
 Tendon
Skeletal Muscles
Major Muscles:
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Mechanics Of
Movements Demo
Cardiac Muscles
Two types of cardiac cells:
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Electrical and myocardial
Heats contracts rhythmically the whole life of an organism.
 Autonomically controlled, involuntary muscle, polarized
 Striated
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Cardiac muscles are auto-rhythmic
 Muscles contract even in the absence of neuronal innervation (pacemaker
cells)
Smooth Muscles
All involuntary actions within body with exception to the heart
 2 types:
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 Visceral smooth muscle
 Multiunit smooth muscle
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No striations due to the absence of sarcomeres
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Some smooth muscle areas include:
 the walls of the viscera, iris of the eye, urinary tract and blood vessels.
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Stimulate movement such as peristalsis
Common Muscular Diseases
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Muscular Dystrophy
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Group of genetic disorders
Muscle weakness and loss of muscle tissue
Gets worse over time
No cure
Sprains and Strains Sprain○ Stretched or torn ligament
○ Ligaments connect bones at the joints
 Strain○ Stretched or torn tendon or muscle
○ Tendons connect the muscle to the bone
Common Muscular Diseases

Myositis
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
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Inflammation of muscle fibers
Swelling of skeletal muscles
Group of diseases
Causes muscle weakness and degeneration
Contraction and Relaxation
Lab
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Sources
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http://www.livestrong.com/article/261129-smooth-muscle-structure/
http://www.andrews.edu/~schriste/Course_Notes/Anatomy__Physiolo
gy__and_Elect/anatomy__physiology__and_elect.html
http://nursingcrib.com/anatomy-and-physiology/anatomy-andphysiology-muscular-system/
http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0002172/
http://www.livestrong.com/article/83692-common-muscular-diseases/
http://healthmad.com/medicine/human-muscular-system/