About 10% of bone is replaced every year in an adult skeleton 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
osteoblasts osteoclasts Maintenance of Bone bone formation bone reabsorption 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 osteoblasts osteoclasts Calcitonin (CT) from thyroid bone formation bone reabsorption osteoblasts osteoclasts Calcitonin (CT) from thyroid Parathyroid hormone (PTH) from parathyroid
Before age 25 osteoblasts osteoclasts Increase bone mass bone formation bone reabsorption osteoblasts osteoclasts Before age 25
bone formation bone reabsorption osteoblasts osteoclasts Age 25-50
Age 50-on osteoblasts osteoclasts Decrease bone mass bone formation bone reabsorption osteoblasts osteoclasts Age 50-on
Stress increases bone density Stress effects bone formation bone reabsorption osteoblasts osteoclasts Stress increases bone density
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