Chapter 9 Muscular System

temporalis

(chewing muscle) flat fan-shaped muscle over temporal bone inserts on mandible. closes jaw, retracts jaw

Frontals

Flat muscle covering forehead, inserts on skin above eyebrows. Raises eyebrows, surprised look, winkles forehead

Name the muscles of the wrist and hand.

Flexor carpi group Extensor carpi group Flexor digitorum Extensor digitorum

Orbicularis oculi

circular muscle around eye, inserts on upper eyelid. Closes eyes, blinking, squinting

Masseter

covers lateral part of lower jaw, origin on maxilla zygomatic process of the temporal bone closes jaw, retracts jaw

sternocleidomastoid

extends along each side of neck

List the muscles of the abdominal wall

external oblique, internal oblique, transverse abdominis, rectus abdominis

buccinator

horizontal cheek muscle, origin on maxilla and mandible. inserts on orbicularis oris. flattens check, trumpeter's muscle, whistling muscle, helps with chewing by positioning food between teeth

zygomaticus

origin of cheekbone, elevates corner of the mouth, smiling muscle

levator palpebrae

origin on bony orbit of eye, inserts on upper eyelid. opens eye

scalenes

origin on cervical vertebrae, inserts on ribs. act synergistically with sternocleidomastoid to flex neck

Name the quadriceps femoris group

rectus femoris, vastus laterals, vastrus medialis, vastus intermedius.

what is the longest muscle in the femur?

satorius

deltoid

thick muscle that covers shoulder joint origin clavical and scapula, inserts on humerus

internal intercostals

between ribs, helps breathing (decreases thoracic cavity in forced exhalation)

Name the hamstrings

Bicepc femoris, semitendinosus, semimembranosus.

Where is the adductor group located and what is their function?

As a group, located on anteromedial structure of the thigh. They adduct and medially rotate thigh, muscles used by horseback riders to stay on horse

What muscles are in the Vertebral column?

Erector spinae Sternocleidomastoid Trapezius Abdominal muscles Iliopsoas

Where is the latissimus dorsi?

Large, flat muscle that covers upper anterior chest. Origin lower vertebral column and lower ribs. inserts on posterior humerus.

Where is the hamstrings located and what are their functions?

Located on posterior surface of the thigh, attaches to ischium insertion on tibia. As a group they flex leg at knee, extend thigh at hip

Name the three muscles in the neck.

Sternocleidomastoid, trapezius, Scalene muscles (three)

With regard to muscle types, what is meant by striated/nonstriated and voluntary/involuntary?

Striated means striped. Nonstriated is smooth. Voluntary means you choose to move it. Involuntary means you do not chose, it works automatically.

List three types of muscle.

Striated/voluntary (skeletal muscle), Non striated/involuntary (smooth muscle), striated/voluntary (cardiac muscle)

What are the rotator cuffs muscles?

Supraspinatus, subscapularis, inframspinatus, teres minor

What muscles are primarily responsible for breathing?

The intercostal muscles and the diaphragm.

What is the function of the deltoid?

abducts arm as in "scarecrow" position flexes, extends, and rotates arm at shoulder

What are the functions of the rotator cuffs muscles?

adduct, extend and rotate arm at shoulder the "cuff" stabilizes shoulder joint.

adductor group

adductor longus, adductor, brevis, adductor magnus

What is the function of the latissimis dorsi?

adducts and rotates arm medially, behind the back. Swimmers muscle.

diaphragm

dome shaped muscle that separates thoracic and abdominal cavities, breathing chief muscle of inhalation (enlarges thoracic cavity)

orbicularis oris

encircles mouth, kissing muscle. purses lips, closes lips

trapezuis

large, flat, trapezoid shaped muscle on back of neck and upper back origin occipital bone, inserts on clavicle and scapula

external intercostals

located between ribs, origin and insertion on ribs (enlarges thoracic cavity during inhalation)

Name the location of the quadriceps femoris group and it's functions

located on anterior thigh, insert on tibia, group used to extend leg at the knee. Rectus femoris can flex thigh at hip. Vastus laterals is common site for intramuscular injections in children