Transcript Muscular System Notes PP

Muscle Tissue Can Contract (shorten) and Relax (lengthen).
This causes mobility and provides support.
1. Allow for movement of:
• skeleton – muscles are connected to bones
• material inside organs (food through digestive
system, blood and materials in blood by pumping
of heart)
2. Provide Support
• Muscles maintain your posture while sitting and
standing
• Muscles stabilize joints
• Muscles help prevent dislocation of bones
Muscles can be:
• Voluntary – you can control
their movement
• Involuntary- you cannot
control their
movement
con
Some can be both – diaphragm, eyelids
1. Skeletal muscle – striated (dark/light fibers), voluntary
2. Cardiac muscle – striated (dark/light fibers), involuntary
3. Smooth muscle – no striations (smooth), involuntary
• Voluntary
• Striated (dark and light bands of
tightly packed fibers)
• Attaches to bone using tendons
• Tendons – connective tissue
that connects muscle to bone
• Many work in pairs (as one
contracts, the other relaxes)
http://www.youtube.com/watch?v=
VCminz-X52I
• Involuntary
• Striated (dark and light bands of
tightly packed fibers)
• Makes up the HEART
• Pumps blood throughout the
body
• A pacemaker in the heart
controls when the muscle
contracts
Heart beat animation
• Involuntary
• NOT striated (smooth)
• Found in many internal organs (esophagus, stomach,
intestines, uterus, diaphragm)
Examples of smooth muscle action:
•Esophagus pushing food to the stomach by peristalsis
•Stomach churning food
•Intestines squeezing food through
•Muscles that makes your pupil contract/dilate
•Diaphragm
•Uterus contracting to go into labor and give birth
Smooth muscle of the intestines
Digestion Video
1. Keep skeletal and cardiac muscles
strong and working properly
2. Helps prevent disease
http://www.brainpop.com/health
/bodysystems/muscles/
Fun MUSCLE Facts:
•
•
•
•
•
•
•
•
•
Contraction of skeletal muscle helps push blood through the veins
Humans have more than 640 skeletal muscles!!
It takes 17 muscles in the face for us to smile and 43 muscles to frown.
If muscle strength is regarded as the ability to use force on something then the
jaw muscle (masseter) is the strongest in the body. The tongue has 8 muscles,
so is technically not the strongest muscle in the body
The gluteus maximus is the largest muscle in the human body.
Muscle memory is created by practicing an action over and over again. Our
muscles fine tune themselves, becoming more precise and exact in what they
do. So practice is very important when learning a sport!!
Skeletal muscle can be further divided into two types, slow twitch and fast
twitch.
Slow twitch (Type I) muscle contain proteins that give it a rich red color. This
muscle carries more oxygen efficiently and using fats, proteins or carbs as
energy, slow twitch muscle fibers contract over a long period of time. Therefore
type I muscle fiber works well for aerobic sports such as long distance running
and cycling.
Fast twitch (Type II) muscle is whiter in color as it has less myoglobin (a oxygen
carrying protein). Fast twitch fibers contract quickly and powerfully, however
they fatigue rapidly. Therefore type II muscle fiber is useful for anaerobic
exercise such as sprinting or for strength sports like weightlifting.