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Bone Remodeling. constant balance of bone deposit and removal that occurs throughout your life bone deposit occurs at a greater rate when bone is injured bone resorption allows calcium of degraded bone matrix to move into the blood. About 10% of bone is replaced every year in an adult skeleton.
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Bone Remodeling constant balance of bone deposit and removal that occurs throughout your life bone deposit occurs at a greater rate when bone is injured bone resorption allows calcium of degraded bone matrix to move into the blood. About 10% of bone is replaced every year in an adult skeleton
Maintenance of Bone boneformation bonereabsorption osteoblasts osteoclasts
Control of Remodeling Hormonal • Rising blood Ca2+levels trigger the thyroid to release calcitonin • Calcitonin stimulates calcium salt deposit in bone • Falling blood Ca2+levels signal the parathyroid glands to release Parathyroid hormone (PTH) • PTH signals osteoclasts to degrade bone matrix and release Ca2+into the blood
Hormonal effects boneformation bonereabsorption osteoblasts osteoclasts Calcitonin(CT)from thyroid Parathyroidhormone(PTH)from parathyroid
Increase bone mass boneformation bonereabsorption osteoblasts osteoclasts Before age 25
boneformation bonereabsorption osteoblasts osteoclasts Age 25-50
Decrease bone mass boneformation bonereabsorption osteoblasts osteoclasts Age 50-on
Stress effects boneformation bonereabsorption osteoblasts osteoclasts Stress increases bone density