Transcript The Muscular System

The Muscular System
Purpose
The main purpose of the Muscular System is movement. Attached
to the bones of the skeletal system are about 700 named muscles
that make up roughly half of the human body weight. Each of
these muscles is made up of muscle tissue, blood vessels, tendons,
and nerves. Muscles also serve to move substances through the
body.
Cardiac Muscle
Anatomy
Skeletal Muscle
Smooth Muscle
• Muscles are a specialized tissue in the human body that can contract and relax. They contract a
lot thus, producing force to different body parts.
• 3 Types Of Muscles are found in the muscular system
• Smooth
• Cardiac
• Skeletal
• Smooth Muscles- Non-striated, Found in soft body organs, responsible for processes
• like digestion of food
• Skeletal Muscles- Striated, Found attached to skeleton, responsible for major
• movements of the body
• Cardiac Muscles- Striated, Found in heart, responsible for pumping activity in heart, very strong
• and tough
Physiology
• The actions your muscular system are controlled by the nervous system, which sends a never-ending stream of
messages along your nerves. When a muscle fiber receives a signal, it will either relax or contract.
• Muscle fibers contain myofibrils, which are cylinders of muscle proteins
• Thick filaments in a muscle are made up of a protein called myosin
• Thin filaments in a muscle are made up of a protein called actin
• During contraction, the myosin thick filaments grab on to the actin thin filaments to form crossbridges
• The thick filaments pull the thin filaments past them, making the sarcomere shorter.
• In a muscle fiber, the signal for contraction is synchronized over the entire fiber so that all of the myofibrils shorten
simultaneously
• Tropomyosin and Troponin are two structures that enable the thin filaments along the thick filaments. Tropomyosin
is long rod-like protein while Troponin is shorter and bead-like.
Relationships
Digestive System- Provides nutrients so muscles can function
Circulatory System- Moves oxygen and glucose around so cells can
work and wastes that can be disposed
Respiratory System- Provides oxygen so muscles can function and
removes carbon dioxide and water that muscle cells produce as a waste
product
Excretory System- Cleans blood of waste products produced by
muscular system
Skeletal System- Works with the muscular system to help the body
with support and movement
Nervous System- Controls the actions of the muscular system by
sending a never-ending stream of messages along the nerves
Medical Problems
Muscular dystrophy- Genetic disease that damages muscle fibers.
Symptoms include weakness, loss of mobility, and lack of coordination.
Cerebral palsy- Impacts posture, balance and motor functions. Brain
damage during or before childbirth causes a loss of muscle tone, making
it difficult to perform everyday tasks.
Myasthenia gravis- A chronic autoimmune disease that results in
muscle fatigue and weakness. A breakdown of neuromuscular junction
causes the brain to lose control over these muscles, which can result in
difficulty breathing or swallowing.
Amyotrophic lateral sclerosis (ALS)- often referred to as “Lou
Gehrig Disease”, is a progressive neurodegenerative disease that affects
nerve cells in the brain. Leads to loss of control over voluntary muscles,
making it increasingly hard to breathe, swallow, or speak.
Fibromyalgia- A chronic disorder characterized by widespread muscle
pain, stiffness, fatigue, and tenderness in localized areas.
Sources
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http://www.montana.edu/craigs/How%20Muscles%20Work.htm
http://www.rsd.edu/schools/carmichael/masters/pdf/hwsystmswrky.pdf
http://www.mananatomy.com/body-systems/muscular-system
http://www.livescience.com/26854-muscular-system-facts-functionsdiseases.html
• http://www.physiologyinfo.org/mm/What-is-Physiology/Muscular/Howthe-Muscular-System-Works.html