| A | B |
|---|
| rickets | expansion of the zone of hypertrophied chondrocytes |
| Fibronectin | Relatively abundant, may help regulate osteoblast differentiation |
| Osteonectin | "Bone connector" may regulate mineralization |
| Thrombospondin | May inhibit bone cell precursors |
| Osteocalcin | Binds calcium |
| Matrix-gla-protein | Inhibits mineralization |
| Bone sialoprotein | Binds to integrins, may assist cancer cells |
| Osteopontin | Increases angiogenesis (makes new blood vessels) which enhances bone resorption in some situations |
| Matrix extracellular protein | May induce a bone disease called osteomalacia |
| Fibronectin knock-out | Lethal |
| Osteonectin knock-out | Osteoporosis |
| Thrombospondin knock-out | Dense bones |
| Osteocalcin knock-out | Bones seem normal |
| Matrix-gla-protein knock-out | Normal bones but calcified blood vessels |
| Osteopontin knock-out | Resistance to PTH and removal of ovaries |
| PTH stimulates | osteoclastic bone resorption indirectly to release calcium from bone. |
| PTH stimulates | stimulates bone formation that is coupled to bone resorption. |
| PTH increases | increases renal tubular reabsorption of calcium. |
| PTH | stimulates the renal production of 1,25 dihydroxyvitamin D to increase calcium absorption from the intestine. |
| PTH enhances | renal phosphate and bicarbonate excretion. |
| A decrease in serum calcium concentration and an increase in serum phosphorous concentration will | stimulate PTH secretion |
| Calcitonin is a peptide hormone | produced by cells within the thyroid gland |
| Calcitonin secretion is stimulated by | high blood calcium concentrations |
| Calcitonin | acts as a physiologic antagonist to PTH |
| Osteoclasts have receptors for … | calcitonin, but the effects of bidning are are transient. |
| Calcitonin inhibits | osteoclast resorption |
| Calcitonin delays | delays calcium absorption from the intestine |
| Calcitonin increases | calcium urinary excretion |
| gastrointestinal absorption of calcium and phosphorus. | Vitamin D promotes |
| is necessary for bone mineralization. | Vitamin D |
| stimulates bone resorption when given in high doses. | Vitamin D |
| Increase bone resorption | Parathyroid hormone |
| Increase bone resorption | Glucocorticoids |
| Increase bone resorption | Thyroid Hormone |
| Increase bone resorption | Vitamin D metabolites in high doses |
| Decrease Bone Resorption | Calcitonin |
| Decrease Bone Resorption | Gonadal Steriods |
| Increase bone formation | Growth hormone |
| Increase bone formation | Vitamin D metabolites |
| Increase bone formation | Gonadal steroids |
| Decrease Bone Formation | Glucocorticoids |
