Signal School
This type of gland releases its products into the bloodstream to act at distant sites.
What is an endocrine gland?
This anterior pituitary hormone stimulates testosterone production by Leydig cells.
What is luteinizing hormone (LH)?
This hypothalamic hormone inhibits growth hormone secretion.
What is somatostatin?
This region of the adrenal gland releases epinephrine and norepinephrine.
What is the adrenal medulla?
ADH is released from the posterior pituitary, but it is synthesized in this location.
What is the hypothalamus?
Name the pancreatic cells that produce insulin and the cells that produce glucagon.
What are pancreatic beta cells producing insulin and alpha cells producing glucagon?
A hormone circulates throughout the body, but only certain cells respond. What must those cells possess?
What is a receptor specific to that hormone?
This ovarian hormone drives proliferation of the endometrium before ovulation.
What is estrogen, especially estradiol?
GH stimulates the liver and other tissues to produce this major mediator of growth
What is insulin-like growth factor 1 (IGF-1)?
Name the anterior pituitary hormone that stimulates cortisol release and the adrenal region it targets.
What is ACTH acting on the adrenal cortex?
Plasma osmolality rises. Predict ADH release and urine concentration in a normal response
What are increased ADH release and more concentrated urine?
Between meals, glucose falls. Predict insulin, glucagon, and hepatic glucose production
What are decreased insulin, increased glucagon, and increased hepatic glucose production?
Steroid hormones bind intracellular receptors. What cellular process does the hormone–receptor complex regulate?
What is gene transcription?
Sustained high estradiol before ovulation changes feedback direction. Name the resulting pituitary event (what hormone increases?).
What is the LH surge?
GH excess develops after epiphyseal growth plates have closed. Would you expect increased height or enlargement of hands and facial features?
What is enlargement of the hands and facial features, or acromegaly?
During stress, cortisol helps maintain blood glucose by increasing this hepatic process.
What is gluconeogenesis?
ADH activates V2 receptors on collecting duct principal cells. Which water channel moves into the membrane?
What is aquaporin-2?
A student says glucagon directly breaks down skeletal muscle glycogen to supply blood glucose. Identify the main target organ instead.
What is the liver?
Although derived from amino acids, this hormone acts through nuclear receptors much like steroid hormones.
What is thyroid hormone?
After ovulation, identify the structure and its major hormone that prepare a secretory endometrium.
What are the corpus luteum and progesterone?
A patient has low thyroid hormone from primary thyroid gland failure. Predict the direction of TSH and explain why.
What is increased TSH due to reduced thyroid hormone negative feedback?
Cortisol is low and ACTH is high. Localize the likely failure to the pituitary or adrenal cortex.
What is adrenal cortex failure, or primary adrenal insufficiency?
Ionized calcium falls. Which hormone rises, and how does it increase intestinal calcium absorption?
What is increased PTH stimulating renal calcitriol production to increase intestinal calcium absorption?
A patient has hyperglycemia, glucose in the urine, and increased urination. Explain how excess blood glucose causes water loss
What is osmotic diuresis caused by glucose in the urine?
Epinephrine can constrict some vessels and dilate others. What best explains these different responses?
What are different adrenergic receptor types on target tissues?
After implantation, which embryonic signal preserves ovarian progesterone production, and which structure does it maintain?
What is hCG maintaining the corpus luteum?
A patient has thyroid hormone excess. Predict heat tolerance and sympathetic responsiveness
What are reduced heat tolerance and increased sympathetic responsiveness?
Why is ACTH deficiency less likely than primary adrenal failure to cause aldosterone deficiency? Name aldosterone’s main regulators.
What is aldosterone regulation primarily by angiotensin II and serum potassium, largely independently of ACTH?
With normal renal function, sustained high PTH tends to raise calcium and lower phosphate. Explain the phosphate change.
What is increased renal phosphate excretion caused by PTH?
During prolonged fasting, the brain can use more ketones. Which blood cells still require glucose, and which hepatic process supplies new glucose?
What are red blood cells requiring glucose and hepatic gluconeogenesis supplying new glucose?