skeletal system

ax-

axis

-blast

bud, a growing organism in early stages

canal-

channel

carp-

wrist

-clast

break

intra-

inside

inter-

among, between

odont-

tooth

poie-

make, produce

arth-

joint

burs-

bag, purse

ov-

egglike

sutur-s

sewing

classifications of bones

long(ex: femur), short(ex: wrist), irregular(ex: vertebrae), flat(ex: ribs), sesamoid(ex: patella)

epiphysis

expanded ends of longbone. Covered w/ articular cartilage.

diaphysis

the shaft of the bone

periosteum

tough, vascular(blood vessels) covering connective fibrous tissue. -muscles attach here.

compact bone

tightly packed tissue-no gaps. gives bone strength.

spongy bone

spaces like a sponge. many branching bony plates called trabeculae.

medullary canal

tube running down the center of diaphysis. lined w/ endosteum.

endosteum

thin membrane containing bone forming cells

red marrow

found in spongy bone, makes blood cell(hematopoietic tissue).

yellow marrow

found in medullary canal=stores fat

major function of bones

support and protect softer tissue, body structure+muscle attachment, blood cell formation, storage of inorganic salts.

blood cell formation=

hematopoiesis

what are ex. of inorganic salts stored in bones

calcium, potassium, sodium, phosphorus, carbonate ions).

osteoblasts

blasts build bone=bone forming cells.

osteoclasts

remodel, destroy the calcifiied matrix.

osteocytes

bone cells in bony chambers called lacunae(were osteoblastes)

central canal(microscopic structures of long bone)=

blood vessels+nerves

canaliculi(microscopic structures of long bone)

bring 02+nutrients

layers(microscopic structures of long bone)

lamellae

surrounds central canal(microscopic structures of long bone)

osteon

primary ossification center

in the center of the diaphysis where bony tissue begins to replace hyaline cartilage.

secondary ossification center

appears later in development inside the epiphyses-spongy bone forms in all directions

band of cartilage left between the 2 ossification centers

epiphyseal disk/plate or metaphysis

vitamin d is necessary for:

proper absorption of calcium in the small intestine(w/o enough calcium, bone is soft, ricekts form). -> found in milk & eggs.

Vit. A and C are required for:

normal bone development and growth.

Vitamin A=

osteoblast and osteoclast activity(carrots)

Vitamin C=

collagen synthesis-osteoblasts need this to make bone matrix(oranges).

growth hormone

pituitary gland

in adults, too much growth hormone causes...

acromegaly(causes body tissues and bones to grow faster)/pituitary gigantism

growth hormone stimulates:

division of cartilage cells w/in metaphysis.

too little growth hormone

pituitary dwarfism

thyroxin

stimulates the replacement of cartilage in metaphysis w/ bony tissue.

parathyroid hormone

stimulate osteoclast activity to help break down bone

sex hormones

promote formation of bone & also stimulate ossification of metaphysis(stop bone lengthening).

physical stress

stimulates bone growth. muscles pull on bones+causes bone tissue to thicken+strengthen. Conversely, lack of exercise causes bones to be thinner+weaker(atrophy).

rib, c-shpaed, rounded, skinny

scapula, looks like heart, flat

clavicle, squigly, skinny

humerus, smaller than femur, big, thick

ulna, space for connection to elbow, has a u

radius, looks like nail, wraps toward fingers

cervical vertebrae, small, skinny, big hole, looks more movable

metacarpal-looks like a hand

lumbar vertebrae-flatter than thoracic, smaller hole

green stick fracture

bends on one side-children

comminuted fracture

shattered

transverse fracture

across the bone

oblique fracture

diagonal break

spiral fracture

twisted

colles fracture

radial break

compound fracture

bone breaks through the skin

simple fracture

bone breaks

joint

an articulation, where two bones come together.

joint classification

based on the type of tissue that binds them

3 types of movement

amphiarthrotic, synarthrotic, and diarthrotic

amphiarthrotic

slightly moveable

synarthrotic

immovable

diarthrotic

freely movable

fibrous joints

held together with dense fibrous connective tissue(CT).

Syndesmosis

bones bound by a sheet or bundle of dense CT. Amphiarthrotic. Between the distal tibia and fibula.

Suture

Only in the flat bones of the skull. Dense CT. = sutural ligament. Synarthrotic. Were fontanets soft spots in infants.

Gomphosis

Joint where a cone shaped bony process fits in a bony socket. Teeth.

Cartilaginous joints

hyaline cartilage or fibrocartilage

Synchondrosis

bones untied by bands of hyaline cartilage, many are temp. & disappear as growth occurs, synarthrotic.

Ex. of synchondrosis

between manubrium of sternum all of the metaphyses(growth plates).

Symphysis

Articular surfaces are covered by a thin layer of hyaline cartliage & is attached to a pad of fibrocartilage. Amphiarthrotic.

Ex. of symphysis

symphysis pubis(2 coxal bones articulate) & between vertebrae.

Synovial joints

Diarthrotic, most bodies of joints, contain articular cartilage, joint capsule, & synovial membrane

Parts of Synovial Joints

articular cartilage, subchondral plate, joint capsule, synovial membrane, synovial fluid, menisci, bursae

Joint capsule

tubular. 1. dense white fibrous CT- fibers attach to periosteum. 2. Ligaments-relatively inelastic, binds bone to bone.

articular cartilage

resistant to wear, prevents friction

subchondral plate

thickened layer of bone, shock absorption and protect joint from body weight and exercise.

synovial membrane

shiny loose CT, lines the synovial cavity

menisci

discs of fibrocartilage between articular surfaces

synovial fluid

clear viscous(thicker) fluid which moistens and lubricates the joint. Supplies the articular cartilage with nutrients.

bursae

fluid filled sacs. commonly found between skin and underlying bony prominences. cushion + aid tendons in movement.

ball and socket

egg shaped ball in a cup sized socket. widest ROM possible.

condyloid joints

(ellipsoidal)oval part in an ellipsoidal cavity. Variety of movement except rotation.

Gliding joints

(Plane). Flat or slightly curved surfaces. Slight back and forth motions.

Hinge joints

convex surface in a concave surface. movement in one plane, like a door.

Ex. of ball and socket joint

Humerus to scapula, femur to coxal.

Ex. of condyloid joint

metacarpals+phalanges

Ex. of gliding joints

carpals, tarsals.

Ex. of hinge joints

ulna to humerus, tibia to femur, all phalanges

Pivot joints

cylindrical surface rotating in a ring of bone or ligament. Rotation around a central axis.

Ex. of pivot joints

C1 to C2, radius to humerus

Saddle joints

have both convex and concoct surfaces. variety of movement in 2 planes.