Chapter 3. The Axial Skeleton (upper body)

axial skeleton

protects major organs of the nervous system, respiratory, and circulatory systems

appendicular sleleton

makes body movements possible; protects the organs of digestion, excretion, and reproduction

upper extremities

shoulders, arms, wrists, and up

lower extremities

hips, thighs, legs, and below

appendage

anything that is attached fo a major part of the body

appendicular

referring to an appendage

An extremity

the terminal end of a body part (arm or leg)

cranium

the portion of the skull that encloses and protects the brain

parietal bones

Two bones forming the roof and upper sides of the skull. Two largest bones in skull

occipital bone

back part of the skull and base of the cranium

external auditory meatus

the opening of the external auditory canal of the outer ear

sphenoid bone

irregular, wedge-shaped bone at the base of the skull

ethmoid bone

Light spongy bone between the eye sockets; forms part of the nasal cavities.

auditory ossicles

the three tiny bones located in each middle ear (malleus, incus, and stapes)

zygomatic bones (cheekbones)

articulate with the frontal bone that makes up the forehead

two maxillary bones

form most of the upper jaw

vomer bone (nasal septum)

cartilage wall that dicides the two nasal cavaties

mandible (jawbone)

only movable bone of the skull

thoracic cavity (rib cage)

bony structure that protects the heart and lungs

costals

ribs

True ribs

first 7 pairs of ribs; attach directly to sternum

false ribs

Ribs 8-12, cartilage conmects them to sternum

Floating ribs

Ribs 11-12, only attached posteriorly to vertebrae, not attached anteriorly

sternum (breastbone)

flat, dagger-shaped bone located in the middle of the chest

Manubrium of sternum

the bony structure that forms the upper portion

body of the sternum (gladiolus)

the bony structure that forms the middle portion

xiphoid process

made of cartilage; forms lower portion of the sternum

pectoral girdle (shoulder girdle)

supports the arms and hands

the clavicle (collarbone)

slender bone that connects the sternum to the scapula

scapula

shoulder blade

acromion

an extension of the scapula that forms the high point of the shoulder

humerus

upper arm bone

radius

smaller and shorter bone in the forearm

ulna

the larger and longer bone of the forearm

olecranon (funny bone)

the large, proximal tip of the ulna

8 carpals

wrist bones

Metacarpals

the 5 bones that form the palms of the hand

Phalanges

14 bones of the fingers & toes

spinal column (vertebral column)

protects the spinal cord and supports the head and body

body of the vertebra

anterior portion of the vertebra is solid to provide strength

lamina

posterior portion of a vertebra

vertebral foramen

opening in the middle of the vertebra

coccyx (tailbone)

end of the spine - 4 small vertebrae that are fused together

sacrum

Triangular bone at the base of the spine.

cervical vertebrae

C1-C7; first set of seven bones, forming the neck

thoracic vertebrae

T1-T12; articulate with ribs, form outward curve of spine

lumbar vertebrae

L1-L5: lower back