Download The Muscular System

The Muscular System
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Muscles make up the bulk of the body and account for about one-third of its
weight. Their ability to contract not only enables the body to move but also
provides the force that pushes substances, such as blood and food through the
body. Without the muscular system, none of the organ systems would be able to
function.
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The skeleton and its joints support, protect, and provide flexibility for the body,
but the skeleton cannot move itself.
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That job is performed y the muscle tissue that makes up the muscular system.
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Approximately 40 to 50 percent of the mass of the human body is composed of
muscle tissue.
Here are three pictures of the muscular skin under a microscope. There are three types of
muscle tissue or muscles:
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Skeletal, smooth, and cardiac
Each type has a different structure and plays a different role in the body.
The Muscular System (Power Point)
- Muscular System Function
Locomotion or mobility, strength, heat production, shock absorption, shaping the body,
maintaining posture, and respiration.
- Muscle Functions
Frontalis - The muscle of the forehead that forms part of theoccipitofrontalis called also
frontalis muscle
Deltoid - a large, triangular muscle covering the joint of the shoulder, the action of which
raises the arm away from the side of the body
Pectoralis - either of two muscles on each side of the upper and anterior part of the
thorax, the action of the larger (pectoralis major) assisting in drawing the shoulder
forward and rotating the arm inward, and the action of the smaller (pectoralis minor)
assisting in drawing the shoulder downward and forward
Biceps - either of two flexor muscles, one (biceps brachii) located in the front of the
upper arm and assisting in bending the arm, and the other (biceps femoris) located on the
back of the thigh and assisting in bending the leg.
Quadriceps - a large muscle in front of the thigh, the action of which extends the leg or
bends the hip joint.
Tibialis Anterior - the inner of the two bones of the leg, that extend from the knee to the
ankle and articulate with the femur and the talus; shinbone.
- Muscular System Teamwork
In addition it plays a role in the digestive process by peristalsis to move the food through.
It is also essential for pumping blood and plays a role in smooth muscles of the blood
vessels to raise blood pressure during the stress response.
Muscles help the body to have mobility through the environment, and motility inside the
body for its processes.
- Muscular System Facts
Muscles are bundles of cells and fibers.
Muscles work in a very simple way. All they do is tighten up--that is, contract--and relax.
You have two sets of muscles attached to many of your bones which allow them to move.
There are 630 active muscles in your body and they act in groups.
Muscles can only pull. They never push.