bone

causes deposition (addition)

causes resorption (breakdown)

tension and pressure

bulbous part of long bone that has hyaline cartilage that covers articulating surfaces

angled edge of epiphysis that leads to diaphysis

• layer of connective tissue capsule that surrounds bone - comes in active or inactive form

active- growing and has two distinct layers-outer fibrous layer and inner cellular layer inactive- not growing and has fibrous layer with reduced cellular inner layer due to the fact that it’s not growing

• dense collagenous connective tissue • has blood vessels, nerves etc that reach bone via perforations • anchored into the bone via sharpey’s fibers

-collagenous bundle fibers that anchor the fibrous layer of the periosteum to the bone

• if covers an actively growing bone: contains OSTEOPROGENITOR CELLS that differentiate into osteoblasts that build bone on THE SURFACE OF BONE • if in inactive bone, it contains PERIOSTEAL CELLS that differentiate into osteoblasts during cell repair

in inactive cellular layer of periosteum that differentiate into osteoblasts during bone repair

articulating bones

• internal connective tissue capsule of the bone • contains a thin inner layer of osteoprogenitor cells that differentiate into BONE LINING CELLS OR OSTEOBLASTS • lines the bone marrow cavity, haversian canal and volkman canal as well as trabeculae of spongy bone

-mineral deposits like calcium phosphate, bicarb, citrate, mg, Na, K

fibers and ground substance that prevent bone from GETTING BRITTLE

collagen type 1 (acidophilic)-stains pink prevents bone from getting brittle

1) proteoglycans with GAGs (hyaluronan, chondroitin sulfate, keratin sulfate that bind growth factors) 2) multiadhesive glycoproteins- osteonectin and sialoproteins 3) bone-specific, vitamin K dependent proteins 4) growth factors and cytokines

• multiadhesive proteins in ground substance of bone (in organic layer • serves as GLUE between collagen (organic) and hydroxyapatite crystals (mineral)(calcium phosphate) in ground organic substance of bone

• osteopontin- helps bind cells to bone matrix - sialoproteins I and II– help bind cells to bone matrix AND begins calcium phosphate formation during mineralization

• a bone-specific vitamin K dependent protein • traps calcium from the blood stream • stimulates osteoclasts to remodel bone

• regulatory proteins • bone morphogenic proteins • induce mesenchymal cells to differentiate into osteoblasts • used following surgery (on large bone defects, spinal fusions etc) to simulate bone formation

• arise from mesenchymal stem cells • resting and reserve cells • located: in mature inner layer of periosteum (called periosteal cells)- inactive • in endosteum- called endosteal cells

inactive osteoprogenitor cells in the inner cellular layer of periosteum

osteoblasts and chondrogenic cells (in low O2)