Download muscular system power point

The Muscular
System
Procedure
Flex your right arm and wrap
your left hand around your
bicep and triceps muscles.
Procedure
Bend and straighten your arm
several times and feel the two
main muscles working under
your skin.
How did the biceps and triceps
change as you bent and
straightened your arm?
When the arm was extended,
the biceps would relax
(lengthen) and the triceps
would contract (shorten). The
reverse happen when the arm
is bent.
• Muscles are the motors
that move body parts
• Bones and joints cannot
move on their own
• There are
approximately 600
muscles in your
body
• 35 – 40% of body mass is
muscle
Functions of the Muscular
System
• pumps blood through your
body.
• moves food through your
digestive system
• allows you to breathe.
• allows you to move.
vocabulary
word!
muscle
• muscle – the tissue that contracts and
relaxes, making movement possible.
vocabulary
word!
voluntary muscles
• voluntary muscles - muscles under
conscious control
– smiling, walking, running, typing etc…
vocabulary
word!
involuntary muscles
• involuntary muscles - muscles not
under conscious control
– You don’t have to think about them
• breathing, digesting, sneezing, heart beating
organs of the muscular system
•
•
•
•
smooth muscle
cardiac muscle
skeletal muscle
tendons
smooth muscle
• smooth muscle – involuntary muscle found in
internal organs and blood vessels and helps
move things around the body.
– blood vessels
– digestive system
smooth muscle
cardiac muscle
• cardiac muscle – involuntary muscle that
makes up the heart. Cardiac muscle cells
have a lot of mitochondria and do not tire.
cardiac muscle
skeletal muscle
• skeletal muscle – voluntary muscle that is
attached to bones and helps you move. Skeletal
muscle can become tired. They work in pairs.
skeletal muscle
vocabulary
word!
tendon
• tendon – tough strand of tissues that connects a
muscle to a bone.
muscles at work
• Skeletal muscle movements are results of
pairs of muscles working together.
– One muscle contracts while the other muscle
relaxes.
– Muscles always pull;
they never push.
muscles at work
muscles at work
• Results of Muscle Action
– Muscles contract
• This produces thermal energy, and it uses
chemical energy.
• Thermal energy produces heat that helps keep
body temperature constant.
• Chemical energy is from glucose. (When
glucose is used up, muscles are tired and need
to rest.)