Bone Tissue-Small stuff

Osteogenic Cell (stem Cell)

Osteoblasts (Matrix synthesizing, responsible for bone Growth)

Osteocyte (mature bone cell)

OSteoclasts (bone resorbing Cell)

Intramembraneous Ossification: forms skull and clavicle during fetal development

Mesenchyme

Forms Osteogenic Cells

osteoblasts

Thickening of Trabeculae

Traps Osteocytes

Blast Activity

Periosteum

Osteoclast Activity ( Molds bone into desired shape)

Endrochondral Ossification of Long Bone: bone develops from hyaline cartilage during fetal developent. Forms bones below skull

Chrondrocytes multiply and mesenchymal cells transform into osteoblasts.

osteoblasts--> perisoteum

Chrondrocytes Die--> Primary Marrow Space

Trabeculae (spongy Bone) formed from osteoblast activity

Medullary Cavity and the diaphysis elongates by osteoblast and osteoclast activity. Cartilage calcified and then eroded

Endrochondral ossification of epiphysis

Similar to steps 1-4 of long bone ossification but periosteum is not formed. Only Spongy bone is formed.

UV Light

Cholesterol--->Vit D

Bloodstream

Liver (Ca levels tell liver to stop producing)

Vit D---> Calcidiol

Kidneys (if needed, PTH can tell it to produce more calcitriol)

Calcidiol---> Calcitriol