Ch. 11 - thyroid-stimulating hormone (TSH) and parathyroid hormone (PTH)
thyrotropin-releasing hormone (TRH) function:
stimulates the release of TSH
thyroid-stimulation hormone (TSH) is also called...
thyrotropin
PTH also stimulates the...
kidneys to conserve calcium
goiter leads to...
low levels of T3 and T4
parafollicular cells release calcitonin which...
maintain blood calcium levels
follicular cells produce T3 and T4 which...
maintain the metabolic rate
parathyroid hormone:
PTH
triiodothyronine is also called...
T3
thyroxine is also called...
T4 or tetraiodothyronine
hypoparathyroidism results in...
a decrease in blood calcium
calcitonin:
a hormone that lowers blood levels of calcium and phosphate ions when they are too high
hyperparathyroidism results in...
an increase in blood calcium
parafollicular cells of the thyroid secrete...
calcitonin
when calcium is high...
calcitonin is secreted
calcitonin secretion is regulated by the blood concentration of...
calcium
hypothyroidism in infants:
causes cretinism: poor growth and bone formation, abnormal mental development, sluggishness
PTH causes activation of vitamin D by kidneys which...
causes increased absorption of calcium in the intestines
hypothyroidism in adults:
causes myxedema: low metabolic rate, fatigue, and weight gain
T3 and T4 are stored in the...
colloids
PTH increases blood calcium ion concentration and...
decreases phosphate ion concentration
hypoparathyroidism:
deficiency of PTH, due to surgical removal or injury to glands
the thyroid hormone level is the major factor in...
determining the basal metabolic rate (BMR)
hyperparathyroidism:
excess of PTH, perhaps due to parathyroid tumor
the parenchyma of thyroid glands contain two types of cells...
follicular cells and parafollicular cells
hyperthyroidism causes:
goiter: enlarged thyroid gland
parathyroid hormone disorders:
hypoparathyroidism and hyperparathyroidism
stimulates --> ________ to release --> ________ which will stimulate the --> ________ to release ________ --> which will stimulate ________ --> to form ________ --> with no ________ to produce T3 and T4 --> the thyroid gland will be ________
hypothalamus, TRH, anterior pituitary gland, TSH, follicular cells, T3 and T4, iodine, enlarged
calcitonin increases calcium excretion by the...
kidneys into urine
BMR stimulates the --> ________ which releases --> ________ which stimulates the --> ________ to secrete --> ________ which stimulates the --> ________ that releases --> ________ which increases --> BMR
hypothalamus, TRH, anterior pituitary gland, TSH, thyroid gland, T3 and T4
thyroid disorders:
hypothyroidism and hyperthyroidism
calcitonin increases calcium deposition in bones by...
inhibiting osteoclasts and stimulating osteoblasts
hyperthyroidism:
overactivity in the thyroid gland
T3 is the most...
potent hormone
T3 and T4 functions:
regulate metabolism of carbohydrates, lipids, and proteins
a negative feedback mechanism involving blood calcium level...
regulates release of PTH
PTH stimulates bone resorption by osteoclasts which...
releases calcium into the blood
as blood concentration of thyroid hormones increases...
secretions of TRH and TSH decrease
basal metabolic rate (BMR):
the caloric intake necessary for life
hypothyroidism:
underactivity of the thyroid gland
