Chapter 4 Muscular System

Muscular System
Major Structures
1. Muscles- my/o. These make the body movement
possible, hold body erect, move body fluids, and
produce body heat.
2. Fascia- Fasci/o, cover, support, and separate
3. Tendons- ten/o, tend/o, tendin/o. Attach muscles
to bone.
4. Aponeurosis- is a flat fibrous sheet of connective
tissue that is similar to a tendon. It attaches
muscle to bone or to other tissues.
Functions of Muscle
1. Muscles hold the body erect and make
movement possible.
2. Muscle movement generates nearly 85 % of the
heat that keeps us warm.
3. Muscles move food through the digestive
4. Muscle movement, such as walking, aids the
flow of blood through veins as it returns to the
5. Muscle action moves fluids through the ducts
and tubes associated with other body systems.
Types of muscle tissue
Skeletal muscles- attach to the bones of the skeleton and are the
muscles that make possible body motions such as walking and
a. they are know as striated muscles because the dark and light
bands in muscles fibers create a striped appearance.
b. they are also know as voluntary muscles because we have
control over them.
2. Smooth Muscles- are located in the walls of internal organs such as
our digestive tract, blood vessels, ect.
a. they are know as Unstriated muscles because they do not have
the dark and light bands that produce striated appearance.
b. These muscles are know as involuntary muscles because they
are under control by our nervous system.
c. Smooth muscles are also know as visceral muscles because
they are found in the large organs and in hollow structures such as
those of the digestive and urinary systems.
3. Cardiac Muscles- also known as the myocardial muscle.
the wall of the heart. My/o means muscle and cardi means heart.
a. Cardiac muscle is a specialized tissue that is like striated muscle
in appearance but like smooth muscle in its action. This muscle
causes the heart to beat and keep us alive.
Characteristics of Muscles
Muscles are arranged in antagonistic pairs, meaning
they work in opposition to each other. Ex. Bicep vs.
tricep because they move elbow joint in opposite
Contraction- is the tightening of a muscle. As the
muscle contracts it becomes shorter and thicker,
causing the belly (center) of the muscle to enlarge.
Relaxation- occurs when a muscle returns to its
original form. Once a muscle relaxes it becomes
longer and thinner. When one muscles pair contracts,
the other usually relaxes.
Muscle tone- also known as Tonus, Is the normal
state of balanced muscle tension that is required to
hold the body in an awake position.
How Muscles are Named
1. Muscle Origin and Insertion- origin is where muscle begins and
insertion is where it ends.
Ex. Sternocleidomastoid.
2. Muscle named by their action- ex. Flexor carpi and Extensor
Carpi muscles
3. Muscles named for their location- ex. Pectoralis major
4. Fiber direction- ex. Rectus abdominis, rectus- means straight
and abdominal means abdomen.
5. By number of division- ex. Biceps brachii, triceps brachii
6. Named for their size- gluteus maximus, means big butt :) or
biggest muscle of the buttocks
7. Named by shape- ex. Deltoid muscle is shaped like an inverted
triangle or the Greek letter delta
1. *Answer these two questions about
Duchenne's and Becker's Muscular Dystrophy.
1. What is the disease and how does it affect the
body? Please tell me how if physically and
mentally effects the body.
2. How do you think this disease would effect the
family involved.
• ROM- Range of Motion
• Abduction- movement away from the mid-line.
Example is an abductor longus in your leg.
• Adduction- movement towards your mid-line.
• Flexion- means to decrease the angle between
two bones that make up the joint.
• Extension- to increase the angle between two
bones at a joint.
• Hyperextension- an extreme of overextension
of a limb at a joint.
• Elevation- raising or lifting a body part, ribs raise
during breathing.
• Depression- act of lowering a body part, ribs
when we exhale.
• Rotation- circular movement around an axis .
• Supination- rotating arm so palm of hand is in
anatomical position.
• Pronation- rotating forearm to where palm is
facing down.
• Dorsiflexion- pulling toes towards head.
• Plantar flexion- calf raise, moving foot down
Medical professionals that
specialize in muscles.
1- Orthopedic Surgeon- treats injuries and
disorders involving bones, joints, muscles, and
2- Rheumatologist- Treats disorders that involve
the inflammation of connective tissue including
3- Neurologist- treats the cause of paralysis and
similar muscular disorders in which there is a
loss of function.
4- Sports Medicine Specialist- treats sports
related injuries of the bones, joints, and muscles.
FascitisTenalgiaTendonitisAdhesion- is a band of fibrous tissue that holds
structures together abnormally.
• Muscle Atrophy- weakness and wasting away of muscle
tissue. Usually after being casted or in a brace for a long
period of time.
• Myalgia• Myolysis- degeneration (break down) of muscle tissue.
My means muscle and lysis means destruction or
breaking down
• Polymyositis- is a chronic, progressive
disease affecting the skeletal muscles.
• Myomalacia• Myorrhexis• Myosclerosis• Hernia- is a protrusion of a part or
structure through the tissues normally
containing it.
• Myocele- is the protrusion of a muscle
through its ruptured sheath or fascia.
• Internet Search these two Muscular
1- Rotator Cuff injuries- Find three different
ones and tell me how they are fixed?
2- Carpal Tunnel Syndrome- Tell me what
the definition is and how it is fixed?
Career Opportunities
Orthopedic Surgeon
Licensed Athletic Trainer
Physical Therapist
Physical Therapy Assistant
Massage therapist
Occupational Therapist
Occupational Therapist Assistant
1. Pick five careers that interest you.
2. Go to
3. Find the following information below for your
five jobs.
• Tell me three schools that I can attend to
obtain this degree
• How many years will it take to obtain this
• What does this license allow you to do?
• How much money can this profession make?
Pathology of Muscle
Starts with Hernia on page 70 and ends with
cardioplegia on page 75.