Exam 2: Endocrine Practice Questions Flashcards
(39 cards)
What is the primary function of the endocrine system?
produce and secrete hormones to regulate physiological processes in order to maintain homeostasis
How do hormones travel through the body to reach their target organs?
Humorally through the bloodstream
What are the three major classes of hormones?
peptide, steroid, amine derived
Which gland is known as the “master gland” and why?
hypothalamus; releases many tropic hormones that produce a cascade of other hormones throughout the body
How do peptide hormones differ from steroid hormones in terms of solubility and receptor location?
- peptide hormones: dissolved in plasma; receptors located on the cell membrane
- steroid hormones: not soluble in blood (bound to carrier proteins); receptors located in the cytoplasm or nucleus of a cell
What hormone is secreted by the pineal gland and what is its major function?
melatonin; regulates sleep cycles based on light available (less light = more melatonin produced)
Which hypothalamic hormones regulate the anterior pituitary?
Growth hormone-releasing hormone (GHRH); Corticotropin-releasing factor (CRF); Gonadotropin-releasing hormone (GNRH); Thyrotropin-releasing hormone (TRH); Dopamine
What are the two hormones released by the posterior pituitary, and what are their primary functions?
- oxytocin: initiates smooth muscle contraction in the uterus and breasts; contractions, let-down reflex
- vasopressin (ADH): increases collecting duct water permeability
How does oxytocin affect the uterus and lactation?
by initiating smooth muscle contraction in the uterus (contractions during labor) and breasts (let down reflex)
What is the role of vasopressin (ADH) in kidney function?
Vasopressin increases water and sodium retention in the nephron
Which hormone promotes milk production in the breast tissue?
Prolactin
What is the function of growth hormone, and what tissues does it primarily target?
Growth hormone stimulates the secretion of insulin-like growth factors from the liver to promote bone and soft tissue growth
How does adrenocorticotropic hormone (ACTH) affect the adrenal cortex?
ACTH increases the production of cortisol in the adrenal cortex
What are the target organs of thyroid-stimulating hormone (TSH)?
Thyroid gland
What are the primary hormones secreted by the thyroid gland?
triiodothyronine, thyroxine, calcitonin
How does calcitonin regulate calcium levels in the body?
calcitonin promotes calcium uptake into bones (promoting osteoblast activity and inhibiting osteoclast activity)
Which hormone regulates plasma calcium levels by increasing calcium resorption from bones?
Parathyroid hormone (PTH)
What hormones are produced by the thymus gland, and what is their role in immunity?
thymosin, thymopoietin
How does atrial natriuretic peptide (ANP) from the heart affect kidney function?
ANP acts as a vasodilator and inhibits renin release which ultimately lowers blood pressure
How do insulin-like growth factors from the liver contribute to growth?
promote bone and tissue growth
What is the primary function of angiotensinogen, and which gland produces it?
angiotensinogen, when activated to be angiotensin, releases aldosterone to increase water and sodium retention to increase blood pressure
What hormones are involved in digestion, and which organs secrete them?
angiotensinogen, gastrin, cholecystokinin, secretin, insulin, glucagon, somatostatin, pancreatic polypeptide
Which hormones are produced by the pancreas, and how do they regulate blood glucose levels?
- insulin: secreted by beta cells in the pancreas after a meal; signals GLUT transporters to migrate to cell membranes to take up glucose
- glucagon: secreted by alpha cells in the pancreas; signals the liver to release glucose into the blood
How do aldosterone and cortisol differ in their function?
- aldosterone: controls sodium and water retention
- cortisol: manages stress, influences metabolism, and regulates blood sugar levels
