Med Term Muscles

Muscles combining form

muscul/o, my/o, myos/o

Muscles function

Make body movement possible, hold body erect, move body fluids, and produce body heat.

Muscles generate body heat

85% of the heat that keeps the body warm

Muscles and digestive system

move food through the digestive system

How do muscles move fluids

movements, such as walking, aid the flow of blood through veins as it returns to the heart, moves fluids through the ducts and tubes associated with other body systems

Interaction of musculoskeletal system

provide the body with form, support, stability, and the ability to move

Fascia combining form

fasci/o

Fascia function

Cover, support, and separate muscles.

Tendons combining form

ten/o, tend/o, tendin/o

Tendon function

Attach muscles to bones.

Bi-

twice, double, two

Clon/o

violent action

Dys-

bad, difficult, or painful

fasci/o

fascia, fibrous band

fibr/o

fibrous tissue, fiber

-ia

abnormal condition, disease, plural of -ium

-ic

pertaining to

kines/o, kinesi/o

movement

-lysis

to set free, break down

my/o

muscle

-plegia

paralysis, stroke

tax/o

coordination, order

ten/o, tend/o, tendin/o

tendon, stretch out, extend, strain

ton/o

tone, stretching, tension

Tri-

three

How many muscles does the body have

more than 600, which make up about 40-45% of the body's weight

Skeletal muscles are made up of

fibers that are covered with fascia and are attached to bones by tendons

Muscle fibers

long, slender cells that make up muscles; each muscle consists of a group of fibers that are bound together by connective tissue.

Fascia (FASH-ee-ah)

a band of connective tissue that envelops, separates, or binds together muscles or groups of muscles; flexible to allow muscle movements

myofascial (my-oh-FASH-ee-ahl) means

pertaining to muscle tissue and fascia (my/o means muscle, fasci means fascia, and -al means pertaining to)

tendon

a narrow band of nonelastic, dense, fibrous connective tissue that attaches a muscle to a bone

Ligaments

are bands of fibrous tissue that form joints by connecting one bone to another bone

Achilles tendon attaches what

gastrocnemius muscle (the major muscle of the calf of the leg) to the heel bone

aponeurosis

a sheet-like fibrous connective tissue resembling a flattened tendon that connects muscles together or to a bone; i.e abdominal aponeurosis

What are the three types of muscle tissue

skeletal, smooth, and myocardial

Skeletal muscles

attached to the bones of the skeleton and make body motions possible

What are skeletal muscles known as

voluntary muscles because we have conscious (voluntary) control over these muscles; striated muscles because, under a microscope, the dark and light bands in the muscle fibers create a striped appearance

Smooth muscles

located in the walls of internal organs such as the digestive tract, blood vessels, and ducts leading from glands;

function of smooth muscles

move and control the flow of fluids through internal organs

What are smooth muscles known as

involuntary muscles because they are under the control of the autonomic nervous system and are not under voluntary control; unstriated muscles because they do not have the dark and light bands that produce the striped appearance seen in striated muscles; visceral muscles because they are found in hollow structures such as those of the digestive and urinary systems

Visceral means

relating to the internal organs

Myocardial muscles (my-oh-KAR-dee-al)

also called myocardium or cardiac muscle, form the muscular walls of the heart (my/o means muscle, cardi means heart, and -al means pertaining to)

How is myocardial muscle similar to smooth and striated

like striated skeletal muscle in appearance but is similar to smooth muscle in that its action is involuntary

Muscle innervation (in-err-VAY-shun)

the stimulation of a muscle by an impulse transmitted by a motor nerve

Motor nerves enable

the brain to stimulate a muscle to contract; when the stimulation stops, the muscle relaxes; control the body's voluntary muscular contractions.

What happens if motor nerve impulses are disrupted

muscle is unable to function properly (i.e paralyzed or unable to contract properly)

Neuromuscular (new-roh-MUS-kyou-lar) means

pertaining to the relationship between a nerve and muscle (neur/o means nerve, muscul means muscle, and -ar means pertaining to)

T or F ; All muscles are arranged in antagonistic pairs

true, means working in opposition to each other, meaning when one contracts, the other relaxes; these contrasting motions that make contraction and relaxation possible

Muscles within each antagonistic pair are made up of

specialized cells that can change length or shape by contracting and relaxing.

Contraction

the tightening of a muscle; muscle becomes shorter and thicker, causing the belly (center) of the muscle to enlarge.

Relaxation

when a muscle returns to its original form; muscle becomes longer and thinner, and the belly is no longer enlarged.

Abduction example

moves the arm away from the body.

Adduction example

moves the arm toward the body.

Extension example

increases the angle of the elbow and moves the hand away from the body.

Flexion example

decreases the angle of the elbow and moves the hand toward the body.

Rotation example

a circular movement around an axis such as the shoulder joint.

Circumduction example

the circular movement at the far end of a limb

Pronation example

turning the arm so the palm of the hand is turned downward.

Supination example

turning the arm so that the palm of the hand is turned upward

Dorsiflexion example

bends the foot upward at the ankle.

Plantar example

flexion bends the foot downward at the ankle

Abduction (ab-DUCK-shun) is the movement of

a limb (arm or leg) away from the midline of the body (ab- means away from, duct means to lead, and -ion means action).

abductor

a muscle that moves a body part away from the midline.

adduction (ah-DUCK-shun) is the movement of

a limb (arm or leg) toward the midline of the body (ad- means toward, duct means to lead, and -ion means action)

adductor

a muscle that moves a body part toward the midline

Flexion (FLECK-shun) means

decreasing the angle between two bones by bending a limb at a joint (flex means to bend, and -ion means action) (knee or elbow is bent)

flexor muscle

bends a limb at a joint

extension means

increasing the angle between two bones or the straightening out of a limb (ex- means away from, tens means to stretch out, and -ion means action) (knee or elbow is straightened)

extensor muscle

straightens a limb at a joint

Hyperextension

the extreme or overextension of a limb or body part beyond its normal limit, hyperextends muscles

Elevation

the act of raising or lifting a body part.

Example of elevation

the levator anguli oris muscles of the face raises the corners of the mouth into a smile.

levator

a muscle that raises a body part

depression

the act of lowering a body part.

Example of depression

the depressor anguli oris lowers the corner of the mouth into a frown.

depressor muscle

lowers a body part

Rotation

a circular movement around an axis such as the shoulder joint; turns a bone on its own axis

axis

an imaginary line that runs lengthwise through the center of the body

circumduction (ser-kum-DUCK-shun)

the circular movement at the far end of a limb

rotator muscle

turns a body part on its axis

Example of rotator muscle

the head of the humerus (HYUM-er-us), which is the bone of the upper arm, rotates within the shoulder joint.

rotator cuff

the group of muscles and their tendons that hold the head of the humerus securely in place as it rotates within the shoulder joint

Supination (soo-pih-NAY-shun)

the act of rotating the arm or the leg so that the palm of the hand or sole of the foot is turned forward or upward

pronation (proh-NAY-shun)

the act of rotating the arm or leg so that the palm of the hand or sole of the foot is turned downward or backward

Dorsiflexion (dor-sih-FLECK-shun)

the movement that bends the foot upward at the ankle

plantar flexion (PLAN-tar FLECK-shun)

the movement that bends the foot downward at the ankle

Plantar means

pertaining to the sole of the foot

superficial muscles

located near the surface, just under the skin

The movements of skeletal muscles are made possible what two points of attachment

origin and insertion

origin

where the muscle begins, and it is located nearest the midline of the body or on a less movable part of the skeleton; the less movable attachment

insertion

where the muscle ends by attaching to a bone or tendon; more movable attachment; the farthest point from the midline of the body.

Example of muscle named for origin and insertion

sternocleidomastoid muscle

sternocleidomastoid muscle movement

helps bend the neck and rotate the head

sternocleidomastoid muscle origin

stern/o, meaning breastbone, and cleid/o, meaning collar bone.

sternocleidomastoid muscle insertion

mastoid muscle inserts at one point of insertion into the mastoid process.

Mastoid process

part of the temporal bone that is located just behind the ear

Example of muscle named for action they allow

flexor carpi muscles and the extensor carpi muscles are the pair of muscles that make flexion (bending) and extension (straightening) of the wrist possible

Carpi means

wrist or wrist bones

Muscle named for location on body or organ they're near

pectoralis major (peck-toh-RAY-lis), for example, is a thick, fan-shaped muscle situated on the anterior chest wall