HSC 214: Superior Muscles and Actions 1-41, Integumentary 1-8

occipitofrontalis

raises eyebrows, wrinkles forehead

epicranial aponeurosis

Tendon that connects the occipitalis and frontalis muscles

buccinator

compresses cheek

Orbicularis oris

closes lips

zygomaticus major

retracts and elevates corner of mouth

orbicularis oculi

closes eye

platysma

tenses skin of neck

temporalis

elevates and retracts mandible

masseter

elevates mandible

digastric

depresses mandible

omohyoid

depresses hyoid

sternohyoid

depresses hyoid

sternothyroid

depresses thyroid cartilage

thyrohyoid

depresses hyoid and elevates larynx

sternocleidomastoid

flexes neck; rotates head

scalene muscles

ORIGIN: transverse processes (C3-C7)

INSERTION: ribs 1-2

ACTION(S): elevates ribs 1-2 during forced inspiration; lateral flexes neck

RELATIONSHIP: consists of three muscles; anterior, middle & posterior

splenius capitis

extends head

semispinalis capitis

extends head, rotates head

central tendon

muscle fibers of the diaphragm converge from its margins into a central fibrous tendon

diaphragm

ORIGIN: diploid process, ribs 5-10, and vertebral bodies (L1-L3)

INSERTION: central tendon

ACTION(S): increases thoracic cavity dimension during inspiration

RELATIONSHIP: primary muscle of respiration; separates the thoracic and abdominopelvic cavities

external intercostals

ORIGIN: inferior border of ribs 1-11

INSERTION: superior border of ribs 2-12

ACTION(S): elevates ribs during inhalation

RELATIONSHIP: oblique muscle fibers that run toward the midline of the body (from superior to inferior)

internal intercostals

ORIGIN: inferior border of ribs 1-11

INSERTION: superior border of ribs 2-12

ACTION(S): depresses ribs during forced exhalation

RELATIONSHIP: oblique muscle fibers that run away from the midline of the body (from superior to inferior)

rectus sheath

Fibrous sleeve enclosing the rectus abdominis

linea alba

midline tendinous seam joining the abdominal muscles

inguinal ligament

a band of connective tissue running from the pubic bone to anterior superior iliac spine

external oblique

compresses abdomen

internal oblique

compresses abdomen

rectus abdominis

flexes vertebral column

transverse abdominis

ORIGIN: iliac crest, inguinal ligament, and costal cartilage of ribs 7-12

INSERTION: pubis, linea alba, and diploid process

ACTION(S): compresses anterior abdominal wall

RELATIONSHIP: horizontal muscle fibers located deep to the rectus abdominis, external and internal oblique muscles

erector spinae

ORIGIN: sacrum, iliac crest, and spinous processes of all vertebrae

INSERTION: transverse and spinous processes of all vertebrae, and occipital bone

ACTION(S): Bilateral - extends neck and vertebral column; Unilateral - laterally flexes and rotates vertebral column

RELATIONSHIP: largest muscle of back; "antigravity" muscle

iliocostalis

lateral erector of spinae muscle

longissimus

middle erector of spinae muscle

spinalis

medial erector of spinae muscles 

multifidus

acts on both the trunk and lies deep to the erector spinae seen best in the lumbar region

quadratus lumborum

makes up the posterior wall of the cavity

laterally flexes vertebral column

deltoid (anterior fascicles)

flex the GH joint.

coracobrachialis

adducts GH joint as an additional action

deltoid (posterior fascicle)

extend the GH joint

latissimus dorsi

lateral muscle of the chest wall (LATS by body builders)

deltoid (middle fascicles)

abduct the GH joint

supraspinatus

ORIGIN: supraspinous fossa

INSERTION: greater tubercle

ACTION(S): abducts shoulder

RELATIONSHIP: S in the "SITS" acronym for the rotator cuff muscles

epidermis

most superficial, avascular layer

stratified squamous epithelium

dermis

composed of dense irregular connective tissue

contains appendages of skin

where ink of tattooos is places

dermal papilla

fingerprints

bumps projecting from the dermis into the undersurface of the epidermis

hypodermis

loose connective tissue primarily composed of adipocytes

separates skin from deep fascia

hair follicle

formation of hair below the surface of the skin

decreases heat loss

arrector pili muscle

ribbon of smooth muscle extending from hair follicle to the dermal papilla

hair follicles become erect when the body is under stress (goosebumps)

sweat (sudoriferous) gland

gland secreting watery fluid to epidermis

produces sweat in response to heat or stress

oil (sebaceous) gland

gland secreting sebum to lubricate and waterproof hair shaft and epidermis

not found in skin of palms or soles