HOSA | Skeletal System

ankyl/o

crooked, bent, stiff

arthr/o

joint

chondr/i, chondr/o

cartilage

cost/o

rib

crani/o

skull

-desis

to bind, tie together

kyph/o

bent, hump

lord/o

curve, swayback, bent

-lysis

loosening/setting free

myel/o

spinal cord, bone marrow

oss/e, oss/i, ost/o, oste/o

bone

scoli/o

curved, bent

spondyl/o

vertebrae, vertebral column, backbone

synovi/o, synov/o

synovial membrane, synovial fluid

-um

singular noun ending

osteoclasts

break down old/damaged bone

osteoblasts

form new bone

periosteum

tough, fibrous tissue covering the outermost part of the bone

compact (cortical) bone

dense, hard bone that forms a protective outer layer

spongy (cancellous) bone

lighter bone than compact, but not as strong

contains red bone marrow

medullary cavity

central cavity of the shaft, contains red + yellow bone marrow

endosteum

tissue that lines the medullary cavity

red bone marrow

hematopoietic tissue that produces RBCs, hemoglobin, WBCs, and thrombocytes (platelets)

hemopoietic/hematopoietic

pertaining to the formation of RBCs

yellow bone marrow

a fat storage area

cartilage

a smooth, rubbery connective tissue that acts as a shock absorber between bones, makes up the flexible parts of the skeleton (outer ear, tip of nose)

articular cartilage

covers the surface of bones where they form joints, protecting joints from rubbing against each other, allows for smooth movement

meniscus

curved, fibrous cartilage found in some joints (eg. knees, jaw)

diaphysis

the shaft of the long bone

epiphysis

the ends of the long bone

foramen

an opening in the bone that allows blood vessels, nerves, and ligaments to pass

process

a surface of the bone that acts as an attachment for muscles/tendons

joints/articulatons

the union point of 2+ bones, classified by construction/the degree of movement they allow

fibrous joint

holds bones tightly together with dense layers of connective tissue

in adults → known as sutures, immovable

in newborns: soft, often moveable before they solidify (eg. fontanelles (soft spots) of a newborn’s skull)

cartilaginous joint

allows minimal movement, consists of bone connected completely by cartilage (eg. where the ribs connect to the sternum, pubic symphysis)

synovial joint

points where 2 bones articulate to allow a variety of motion, described based on type of motion

ball and socket joint

type of synovial joint, allows a wide range of movement (eg. shoulders, hips)

hinge joint

allows movement in a single direction/plane (eg. elbows, knees)

synovial capsule

outermost layer of strong, fibrous tissue that surrounds the joints like a sleeve

synovial membrane

lines the synovial capsule, secretes synovial fluid

synovial fluid

a lubricant within the synovial capsule that allows for smooth movement

ligaments

bands of fibrous tissue that connect bones → each other/bones → cartilage

bursa

fibrous sac that cushions + reduces friction in a joint where a tendon passes over a bone (eg. shoulder, elbow, knee)

axial skeleton

protects the major organs of the neurological, respiratory, and circulatory system

consists of 80 bones in the head + trunk

bones of the skull, ossicles of the middle ear, hyoid bone, ribcage, and the vertebral column

appendicular skeleton

allows movement, and protects the major organs of digestion, excretion, and reproduction

consists of 126 bones in the extremities, including upper extremities (arms, wrists, hands) and lower extremities (legs, ankles feet)

how many bones form the skull?

28

cranium

made of 8 bones; part of skull that encloses and protects the brain, joined by sutures

frontal bone

anterior portion of the cranium, that forms the forehead

parietal bones

forms roof + upper sides of cranium; 2 of the largest skull bones

occipital bone

forms the back of the skull + base of the cranium

temporal bone

forms sides and the base of the cranium

external auditory meatus

opening of the external auditory canal of the outer ear

sphenoid bone

irregular, wedge-shaped bone at the base of the skull; forms the base of the cranium, and the floors + sides of the eye sockets

ethmoid bone

light, spongy bone on root + sides of the nose, forms a portion of each orbit (bony socket that surrounds eyeballs)

auditory ossicles

3 tiny bones in each middle ear (malleus, incus, and stapes)

how many bones form the face?

14; some contain sinuses (air-filled cavities)

nasal bones

form the upper part of the bridge of the nose

zygomatic bones (cheekbones)

articulate with the frontal bone

maxillary bones (maxillae)

form most of the upper jaw

palatine bones

form anterior part of hard palate of the mouth + floor of the nose

lacrimal bones

make up part of the orbit at the inner angle

inferior conchae

scroll-like bones that form part of the interior of the nose

vomer bone

forms the base of the nasal septum

nasal septum

cartilage wall that divides the 2 nasal cavities

mandible (jawbone)

the only movable bone of the skull, attached to the skull at the temporomandibular joint (TMJ)

thoracic cavity

ribcage, bony structure that protects the heart + lungs

includes the ribs, sternum, + upper portion of the spinal column from neck to diaphragm

how many ribs are there?

12 pairs of ribs (costals) that attach posteriorly to thoracic vertebrae

true ribs

first 7 pairs of ribs, attach anteriorly to the sternum

false ribs

next 3 pairs of ribs after the true ribs, attach anteriorly to cartilage that connects them to the sternum

floating ribs

last 2 pairs of ribs, attach posteriorly to the vertebrae

sternum

breast bone; flat, dagger-shaped bone in the middle of the chest, forms front of ribcage

manubrium

bony structure that forms the upper portion of the sternum

body of the sternum

bony structure that forms the middle portion of the sternum

xiphoid process

structure made of cartilage that forms the lower portion of the sternum

shoulders

form the pectoral girdle, which supports the arms and hands

includes clavicle, scapula, and acromion

clavicle

collar bone; slender bone that connects the manubrium of the sternum to the scapula

scapula

shoulder blade

acromion

extension of the scapula, forms the highest point of the shoulder

humerus

the bone of the upper arm

radius

the smaller + shorter bone in the forearm, runs up the thumb side of the forearm

ulna

the larger + longer bone of the forearm; proximal end articulates w/ the distal end of the humerus to form the elbow joint

olecranon process (funny bone)

large projection on the upper end of the ulna

carpals

bones that form the wrist, forms narrow bony passage known as the carpal tunnel

metacarpals

5 bones that form the palms of the hand

phalanges

14 bones of the fingers; each finger has 3 bones (distal, middle, + proximal), thumb has 2 bones (distal + proximal)

spinal column

protects spinal cord + supports the head and body

body of the vertebra

anterior portion of the vertebra that provides strength

lamina

posterior portion of a vertebra, serves as attachments for muscles + tendons

vertebral foramen

opening in the middle of the vertebra, allowing the spinal cord to pass through

intervertebral disks

made of cartilage, separates + cushions vertebrae from each other, act as shock absorbers, allow for movement of the spinal column

cervical vertebrae

C1 to C7; 1st set of 7 vertebrae, forming the neck

thoracic vertebrae

T1 through T12; 2nd set of 12 vertebrae

lumbar vertebrae

L1 through L5; 3rd set of 5 vertebrae

sacrum

slightly curved, triangular-shaped bone near the base of the spine

coccyx

tailbone, forms the end of the spine

pelvic girdle

pelvis, hips; protects internal organs + supports the lower extremities

ilium

broad blade-shaped bone that forms the back + sides of the pubic bone

sacroiliac

slightly movable articulation between the sacrum + posterior portion of the ilium

ischium

forms the lower posterior portion of the pubic bone, bears the weight of the body when sitting

pubis

forms the anterior portion of the pubic bone, located just below the urinary bladder