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
a process in which the absence of a hormone triggers an increase in the number of hormone receptors; cells are more sensitive when hormone levels are low
up-regulation
slender, funnel-shaped structure connecting the pituitary gland to the hypothalamus
infundibulum
stimulates the synthesis and secretion of one or more hormones at the adenohypophysis
releasing hormone
prevents the synthesis and secretion of hormones from the adenohypophysis
inhibiting hormone
this effect results from an increased metabolic rate of cells, increased energy consumption of cells, and increased heat generation
calorigenic effect
an adrenal gland
suprarenal
a type of diabetes mellitus in which insulin levels are normal or elevated, but peripheral tissues no longer respond normally
type 2 diabetes mellitus
a type of diabetes mellitus primarily caused by inadequate insulin production by the beta cells of the pancreatic islets
type 1 diabetes mellitus
the pattern of hormonal and physiological adjustments with which the body responds to all forms of stress
General adaptation syndrome (GAS)
when two hormones have additive effects so that the net result is greater than the effect that each would produce acting alone
synergistic effect
occurs when the first hormone is needed for the second to produce its effect
permissive effect
occurs when hormones produce different but complementary results in specific tissues and organs
integrative effect
energy reserves are mobilized, mainly in the form of glucose, and the body prepares to deal with the stress-causing factor by “fight or flight” responses
alarm phase
occurs when stress lasts longer than a few hours; dominated by glucocorticoids; lipid and protein reserves are mobilized, glucose is conserved for neural tissues, blood glucose concentrations are elevated and stabilized, salts and water are conserved while potassium and hydrogen are lost
resistance phase
the eventual breakdown of homeostatic regulation and failure of one or more organ systems
exhaustive phase
a condition caused by the hyposecretion of glucocorticoids and mineralcorticoids; characterized by an inability to mobilize energy reserves and maintain normal blood glucose levels
Addison disease
