Term
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Definition
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Definition
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Definition
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Definition
| Helps strengthen bond ECM |
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Term
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Definition
| Activates enzymes involved in synthesis of bone ECM |
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Term
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Definition
Needed for activity of osteoblasts during remodeling of bone;
deficiency stunts bone growth;
toxic in high doses |
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Term
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Definition
Needed for synthesis of bone proteins;
deficiency leads to abnormal protein production in bone ECM and decreased bone density. |
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Term
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Definition
Needed for synthesis of collagen, the main bone protein;
deficiency leads to decreased collagen production, which slows down bone growth and delays repair of broken bones. |
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Term
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Definition
Active form (calcitroil) produced by kidneys;
increases absorption of calcium from GI tract;
Deficiency causes faulty calcification and slows bone growth;
may reduce risk of osteoporosis but toxic in high doses;
also obtained from sun exposure.
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Term
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Definition
Needed for synthesis of bone proteins;
deficiency leads to abnormal protein production in bone ECM and decreased bone density. |
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Term
| Human Growth Hormone (hGH) |
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Definition
Secreted by the anterior lobe of the pituitary gland;
promotes general growth of all body tissues, mainly by stimulationg production of insulinlike growth factors |
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Term
| Insulinlike Growth Factors (lGFs) |
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Definition
| Secreted by liver, bones, and other tissues upon stimulation bt hGH, promotes normal bone growth by stimulating osteoblasts, and by increasing synthesis of proteins needed to build new bone. |
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Term
Thyroid
(thyroxine and triiodothyronine) |
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Definition
| Secreted by thyroid gland; promote normal bone growth by stimulating osteoblast |
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Term
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Definition
| Secreted by pancreas; promotes normal bone growth by increasing synthesis of bone protiens |
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Term
Sex Hormones
(Estrogen and Testosterone) |
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Definition
Ovaries (estrogen);
Testes (testosterone);
Stimulates osteoblasts, promotes growth during puberty; shut down at epiphyseal plates around ages 18-21, causing lengthwise growth of bones to end;
Contribute to bone remodeling during adulthood by slowing bone resorption by osteoclasts and promoting bone deposition by osteoblasts. |
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Term
Parathyroid Hormone
(PTH) |
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Definition
Secreted by parathyriod glands;
promothes bone resorption by osteoclasts;
enhances recovery of calcium ion from urine;
promotes formation of active form of vitamine D (calcitriol) |
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Term
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Definition
Secreted by thyroid gland;
Inhibits bone resorption by osteoclasts |
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Term
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Definition
| Weight-bearing activities, stimulate osteoblasts, and consequently help build bigger, stronger bones and retard loss of bone mass that occurs as people age |
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Term
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Definition
| Decreases in sex hormones (especially in women after menopause) causes the pace of bone resorption to outpace bone deposition, resulting in a decrease in overall bone mass, which increases risk of osteoperosis. |
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