Download THE MUSCULAR SYSTEM CHAPTER 15

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FUNCTIONS:
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Body Movement
Pump Blood Throughout body
Move food through digestive system
Control air movement in and out of the lungs
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CONTRACTION: Shortening of a muscle.
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EXTENSION: stretching of a muscle.
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Muscles work in opposition, while one
contracts, the other extends.
Antagonistic = work in opposition, muscles
do this, so one muscle would be the
antagonistic muscle to another one.
Examples = bicep/triceps
quadriceps/hamstrings
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SMOOTH MUSCLE: control movements of
internal organs.
◦ Involuntary movements…work without conscious
control.
◦ Intestines, bronchi of the lungs, the bladder.
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SKELETAL MUSCLE: striped or striated
muscles attached to the bones that cause
body movement.
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Biceps, triceps.
Largest part of the body’s muscular system.
Voluntary movements, conscious control.
FLEXORS: muscles that close a joint.
EXTENSORS: muscles that open a joint.
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CARDIAC MUSCLE: striated tissue that forms
the wall of the heart.
◦ Involuntary muscle.
◦ Heart contracts rhythmically about 100,000 times a
day.
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ATROPHY: waste away (“Use it or lose it”)
MUSCLE TONE: the natural tension in the fibers of a
muscle.
◦ Aerobic exercise, resistance training, balanced diet.
◦ Older adults…prevent loss of mobility, balance, and risk of
falls.
◦ The heart is a muscle that needs “training”…regular
exercise.
◦ Stretching, warm-up, cool down.
◦ As always safety.
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MUSCLE SORENESS:
damage to the muscle
fibers themselves. Muscle
biopsies taken on the day
after hard exercise show
bleeding and disruption of
the z-band filaments that
hold muscle fibers
together as they slide over
each other during a
contraction.
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MYASTHENIA GRAVIS: muscles
become weak and easily fatigued.
◦ Eye muscles…drooping eyelids and
double vision.
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MUSCULAR DYSTROPHY: inherited
disorder characterized by a
progressive wasting away of
skeletal muscles.
◦ No cure.
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MUSCLE
STRAIN:
“pulled
muscle”,
tearing or
stretching of
muscles fibers
as a result of
suddenly
pulling them to
far.
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BRUISE:
discolored area
under the skin
caused by a
leakage of
blood after an
injury.
After Femur fracture
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TENDINITIS: the
inflammation of a
tendon, usually
caused by overuse.
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HERNIA: the
protrusion of an
organ of tissue
through a weak
area in the
muscle.
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Cartilage = allows smooth movement at a
joint – connects the ribs and is a cushion
between vertebrae.
Ligaments = connect bone to bone at a joint.
Tendons = a band of fiber that connects
muscles to bones.
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Muscle tissue is
◦ ¾ water
◦ The remaining ¼ is
 20% protein
substances
 5% nonprotein and
mineral substances.
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What is ATP?
◦ Adenosine Triphosphate is a
nonprotein chemical substance in
muscle tissue. It is a source of
immediate energy for muscle
contraction.
What is Glycogen?
- An organic compound in muscles.
Stored in cells and used as the body
needs energy.