Tracie Haan
M.E. Meyerhofer
Chelsea Friesen
Muscular System
Muscular System
Physiology

4 main functions of the muscles:

Produces movement

Maintain posture

Reinforces and stabilizes joints

Generates heat
Muscle Types
 There
are three main
muscle types:
Skeletal
 Cardiac
 Smooth

Skeletal Muscles
The four primary functions of skeletal muscles:

 Movement
 Posture
 Support
 Heat regulation

Controlled under somatic nervous system

Voluntarily Controlled

Striated

Most skeletal muscles are attached to bones

by bundles of collagen fibers known as tendons.
Skeletal Muscle Structure

Skeletal Muscle Cells (myocytes)
 myoblasts
○ Myofibrils

Skeletal Muscles
 Belly
○ Fascia:
 Epimysium
 Perimysium
 Endomysium
○ Muscle Fiber (Cell)
 Tendon
Skeletal Muscles
Major Muscles:
66
Mechanics Of
Movements Demo
Cardiac Muscles
Two types of cardiac cells:


Electrical and myocardial
Heats contracts rhythmically the whole life of an organism.
 Autonomically controlled, involuntary muscle, polarized
 Striated


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:

 Visceral smooth muscle
 Multiunit smooth muscle

No striations due to the absence of sarcomeres

Some smooth muscle areas include:
 the walls of the viscera, iris of the eye, urinary tract and blood vessels.

Stimulate movement such as peristalsis
Common Muscular Diseases

Muscular Dystrophy




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



Inflammation of muscle fibers
Swelling of skeletal muscles
Group of diseases
Causes muscle weakness and degeneration
Contraction and Relaxation
Lab
12
Sources






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/