Transcript Human Biology 1.3

The muscular system makes
movement possible.
The human body is made up of
systems that work together to
perform necessary functions.
Muscles are involved in
every movement of the
body.
Muscles are made of
individual cells called
muscle fibers.
Muscles perform important functions.
Each muscle fiber or
strand can contract or
stretch.
Muscles allow your
body to move, to
generate heat, and to
maintain posture.
The muscular system works with the skeletal
system to allow movement.
Individual cells, called muscle fibers, contract and relax.
Muscles are attached to bone by stretchy connective
tissue, and, working in pairs, they contract and relax to
move the body.
Muscles assist in homeostasis by functioning to maintain
body temperature.
When muscles contract they release heat, so the quick
muscle contractions that occur when you shiver release
heat and raise your body temperature.
Muscles make constant, automatic, tiny adjustments to
keep you sitting or standing upright.
The muscles that maintain posture are only completely
relaxed when you are unconscious.
The body has three types of muscles.
Skeletal muscles are
attached to the
skeleton.
Smooth muscle are
found inside certain
organs
Cardiac muscle is
found in the heart.
Definition:
attached to the skeleton
Example:
Leg muscles
Characteristics:
Perform voluntary
movement
Skeletal
Muscles
Nonexample:
Heart muscles
Definition:
Characteristics:
Muscles that move when
Made of long fibers
you want them to.
Voluntary
Muscles
Example:
Leg muscles
Nonexample:
Smooth muscle
Smooth Muscles
Smooth muscles are the muscles that perform automatic
movement inside the intestines and the stomach.
Smooth muscles are involuntary, while skeletal muscles
are not.
Smooth muscles are found in organs while skeletal
muscles are attached to the skeleton.
Definition:
Characteristics:
Muscle the heart is made
Has a branched shape
of.
Cardiac
Muscle
Example:
Nonexamples:
The muscle cells in the
Stomach muscles
heart
Skeletal muscles and tendons allow
bones to move.
The tendon is the link between the muscle and the bone.
When a muscle contracts, it pulls on the tendon, which
pulls the bone.
During early childhood
muscles are not yet well
developed.
As humans grow older,
muscles develop and
become more
coordinated.
Muscles grow and heal.
Regular exercise
increases muscle size.
Sore muscles indicate
damaged muscle fibers.