The
Muscular System
Muscle System Functions
• Provides voluntary movement of body
– Enables breathing, blinking, and
smiling
– Allows you to hop, skip, jump, or do
push-ups
• Maintains posture
• Produces heat
• Causes heart beat
• Directs circulation of blood
– Regulates
blood
pressure
blood
pressure
– Sends blood to different areas of
the body
• Provides movement of internal organs
– Moves food through digestive tract
– Enables bladder control
• Causes involuntary actions
– Reflex actions
– Adjusts opening of pupils
– Causes hair to stand.
Muscle Tissue Characteristics
•
Is made up of contractile fibers
•
Provides movement
•
Controlled by the nervous system
–
Voluntary- consciously controlled
–
Involuntary- not under conscious
control
•
Examples:
Skeletal, Smooth, Cardiac
Comparison
of Muscle Types
Muscle
Tissue Anatomy
Production of Energy for Muscle
•
ATP (adenosine triphosphate)
–
A type of chemical energy
–
Needed for sustained or repeated
muscle contractions
•
Muscle cells must have three ways to
store or make ATP
–
Creatine phosphate
• Rapid
production of energy
–
Aerobic respiration
• Uses
body’s store of glucose
–
Lactic acid
production
Small amounts of ATP
Mechanics of a Muscle Contraction
•
When each sarcomere becomes shorter
it causes each myofibril to become shorter.
•
When each myofibril becomes shorter it
causes the
muscle fibers
to become shorter
0 komentar:
Posting Komentar