DIAGRAM: BONE: Endochondral ossification bone growth series, 7-12 of 14; A=Primary Trabeculae, B=Bone Marrow, C=Cartilage, D=Secondary Spongiosa, E=Primary Ossification Center, F=Secondary Ossification Center, G=Bone, H=Epiphyseal Plate, I=Articular Cartilage -- PICTURE 7-Pluripotent cells from the perivascular