Bone/Cartilage

compact bone

forms dense, hard outer casing of all bones

composted of osteons

resists forces from weight and movement

spongy bone

forms light, thin inner network of bone

can resist stress in multiple directions, found within flat bones and at the ends of long bones

hematopoiesis

protection in blood cells

occurs in red bone marrow in some spongy bone

adult

red bone marrow restricted to axial skeleton

yellow bone marrow in long bone shafts

child

red bone marrow in some spongy bone

long bones

lever, joints, and pivots for body movement

cylindrical bone shaft

short bones

distribute and transfer forces across multiple bones

flat bones

broad surface for muscle attachment and provide protection

irregular bones

varied function including attachment and protection

diaphysis

cylindrical shaft

compact bone with medullary cavity

epiphysis

ends of the bone

outside layer of compact bone surrounding spongy bones

articular cartilage

hyaline cartilage on the epiphyses

supports, provides smooth surface for join movement

osteoartritis

articular cartilage wear down, bone rubs against bone

epiphyseal plate

hyaline cartilage plate between diaphysis and epiphysis

epiphyseal line

thin plate of compact bone between epiphysis

periosteum

dense irregular CT and cell layer that covers outside of bone

NOT found on articular surfaces of bones

grows in bone width

perforating fibers

very vascular, lots of nerves to anchor periosteum to bone

osteoblasts

immature bone cells that create bone

secrete osteoid

osteocytes

mature bone cells that maintain one matrix

osteoclasts

break down and reabsorb bone

formed from fused red bone marrow cells; large

osteons

compact bone is made up of…

spongy bone is not made up of…

central canal

opening that contains blood vessels/nerves

concentric lamellae

concentric rings of bone matrix

lacunae

spaces where osteocytes reside

canaliculi

tiny channels that radiate from lacunae

perforating canal

run perpendicular to the central canals; connect multiple central canals

interstitial lamellae

incomplete remnants of osteons

circumferential lamellae

rings of bone that run the entire circumference of the shaft

ossification

formation and growth of bone tissue

intramembranous ossification

pre-existing tissue is mesenchyme into flat bones

endochondral ossification

pre-existing tissue is hyaline cartilage to form most bones

fracture hematoma

fibrocartilaginous callus

bony callus

remodeling

periosteum

covers the outer surface of the bone, except for areas covered by articular cartilage

osteocyte

osteoblast

osteoclast

lacunae

space

osteon

central canal

lamella

canaliculi

osteocyte

cell

endosteum

cover all internal surfaces of the bone, such as medullary cavity