Term
| What is needed for Growth? |
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Definition
| Cell division and differentiation, nutrition, bone growth, hormones |
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Term
| What does an epiphyseal growth plate do? |
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Definition
| add more bone to grow in its length |
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Term
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Definition
| bone forming cells, convert cartilaginous material to bone |
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Term
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Definition
| synthesize more new cartilage in interior of the plate. |
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Term
| What are the hormones for growth? |
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Definition
| GH, Insulin-like growth factor- I, thyroid hormone, insulin, testosterone, estrogens, peptide growth factors, peptide growth-inhibiting factors. |
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Term
| What does growth hormone do? |
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Definition
| Stimulates cell division in many target tissues, stimulates maturation and cell division of chondrocytes in the epiphysal plates for bone growth. Indirect effect of growth hormone. |
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Term
| What is the indirect effect of GH? |
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Definition
| stimulate many cells to secrete IGF-1,. Liver: IGF-1 as hormone. Bone cells: IGF-I as autocrine and paracrine. |
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Term
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Definition
| Growth hormone insensitity hormone. Normal GH level in blood. Unresponsive to GH due to growth hormone receptor mutation. Low serum level of IGF-1 due to inability of GH to send signals. |
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Term
| T/F. Laron Syndrome dwarfism of GH will respond to exogenous GH injection. |
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Definition
| False. It is a mutation in the GH receptor. |
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Term
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Definition
| protein synthesis in skeletal muscle. Anti-insulin effects. |
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Term
| T/F. GH has a large effect on the growth of embryo and fetus. |
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Definition
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Term
| Protein synthesis in skeletal muscles because of GH. |
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Definition
| causes an increase in amino acid uptake and he synthesis and activity of ribosomes. |
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Term
| Regulation of Growth Hormone |
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Definition
| Secretion occurs in episodic bursts and follows daily rhythm, stimuli which increase GH: stress, hypoglycemia, exercise; Feedback inhibition |
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Term
| GH secretion during life span |
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Definition
| largest in adolescence, 2nd largest in children, lowest in adults. |
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Term
| Feedback inhibition of GH |
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Definition
| GH on hypothalamus, IGF-1 on Anterior pituitary gland and hypothalamus |
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Term
| Stimuli which increase GH secretion |
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Definition
| stress, hypoglycemia, exercise |
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Term
| T/F. Thyroid Hormone will stimulate synthesis of GH effect on growth |
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Definition
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Term
| T/F Insuline promotes cel differentiation and cell division |
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Definition
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Term
| Sex Hormone effects on growth |
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Definition
| Stimulates secretino of GH and IGF-1; rsponsible for inducing the closure of epiphyseal growth plate; testosterone: protein synthesis in many organs; Anabolic steroids: used for building muscle mass. |
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Term
| What are some of the toxic effects of sex hormone? |
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Definition
| liver damage, risk of prostate cancer, infertility. |
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Term
| Cortisol effect on growth |
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Definition
| has anti-growth effect, inhibits DNA synthesis * promotes protein catabolism, bone resorption, inhibits secretion GH. |
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Term
| Cause of Chronic Excess of Growth Hormone |
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Definition
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Term
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Definition
| caused by hypersecretion of GH after puberty, thickening many bones in the body. Hands, feet , nose and head, internal organs are enlarged: heart and tongue. diabetic like symptoms: high blood glucose and FFA. |
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Term
| What are the effects of low plasma (Ca2+)? |
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Definition
| incerased excitability of nerve and muscle plasma membrane. |
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Term
| What are the effects of high plasma Ca2+? |
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Definition
| cardiac arrhythmia, depressed neuromuscular excitability. |
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Term
| Effector sites for Ca2+ hoemostasis. |
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Definition
| Bone, kidney, GI system. 99% if body Ca2+ is in bones. |
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Term
| Hormones favoring bone formation |
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Definition
| insulin, GH, IGF-1, Estrogen, Testosterone, calcitonin |
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Term
| Hormones favoring bone resorption |
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Definition
| Parathyroid hormone, cortisol, thyroid hormone (T3 & T4) |
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Term
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Definition
| small endocrine gland located on neck behind the thyroid, no relationship with thyroid gland, produces PTH, which controls Ca2+ in blood, not influenced by anterior pituitary gland. |
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Term
| T/F. Parathyroid gland is influenced b anterior pituitary gland. |
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Definition
|
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Term
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Definition
| low Ca2+ turns on & increases PTH. High blood Ca2+ turns off & lowers PTH. |
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Term
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Definition
| secreted from para-follicular cells within thyroid cells. distinct from tyroid follicles. increased Ca2+ causes the secretino of calcitonin. inhibits activity of osteoclasts, resulting in a decrease in plasma Ca2+. does not regulate day-to-day variation of plasma Ca2+ |
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Term
| T/F Calcitonin regulates day-to day variation of plasma Ca2+? |
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Definition
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Term
| Hyperfunction of parathyroid gland |
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Definition
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Term
| Primary Hyperparathyroidism |
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Definition
| parathyroid adenoma, primary parathyroid hyperplasia. |
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Term
| Secondary Hyperparahtyroidism |
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Definition
| compensatory rsponse to hyperphosphatemia due to renal disease, decreased absorption of vitamin D, decreased production of 1,25 dihydroxyvitamin D. may lead to bone disease due to continuous bone resorption. |
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Term
| What are the clinicla features of hyperparatyroidism |
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Definition
| elevated PTH, increase in Ca2+, bone decalcification, osteoporosis, prone to fracture, deposition of Ca2+ on kidney formation of kidney stone, depresion, poor memory, lethargy, muscle weakness, peptic ulcer; due to increase in gastric acid with hypercalcimic-induced increase in serum gastrin, muscle atrophy due to peripheral neuropathy. |
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Term
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Definition
| inadvertent removal of parathyroid gland during cancer surgery. hypocalcemia, nueromuscular irritability: muscle becomes spasti(hypocalcemic tetany), cardiac arrhythmias. |
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