Ch. 18 Vocab Flashcards
a condition caused by hypothyroidism at birth or in infancy; marked by inadequate skeletal and nervous system development and a metabolic rate as much as 40% below normal levels
cretinism
a condition caused by the hypersecretion of glucocorticoids; characterized by the excessive breakdown and relocation of lipid reserves and proteins
Cushing disease
a disorder that develops when the neurohypophysis no longer releases adequate amounts of ADH, or when the kidneys can’t respond to ADH
diabetes insipidus
the presence of glucose in the urine
glycosuria
an abnormal enlargement if the thyroid gland
goiter
abnormally high blood glucose levels
hyperglycemia
muscle spasms affecting the face and upper extremities; caused by low Ca2+ concentrations in body fluids
hypocalcemic tetany
condition resulting from severe hyposecretion of thyroid hormones; characterized by subcutaneous swelling, hair loss, dry skin, low body temperature, muscle weakness, and slowed reflexes
myxedema
the production of excessive amounts of urine; a sign of diabetes
polyuria
a condition characterized by depression, lethargy, an inability to concentrate, and altered sleep and eating habits; linked to elevated melatonin levels in individuals exposed to only short periods of daylight
seasonal affective disorder (SAD)
pituitary gland
hypophysis
specific cells that possess the receptors needed to bind and “read” the hormonal message when it arrives
target cells
hormones that bind to receptors in the plasma membrane; can’t have a direct effect on the activities inside the target cell; leads to the appearance of a second messenger
first messenger
may act as an enzyme activator, inhibitor, or cofactor; regardless, the result is a change in the rates of various metabolic reactions
second messenger
a process in which the presence of a hormone triggers a decrease in the number of hormone receptors; cells are less sensitive to higher hormone levels
down-regulation