Lecture 20: Endocrine System - Pituitary and Adrenal Glands Flashcards
define “ex”
out
define “krinein”
to secrete
define “endo”
within
functions of exocrine glands
secrete secretions into ducts which carry the secretions out of glands into lumens of certain places of the body
functions of endocrine glands
secrete sectretions right into spaces around cells; the products are picked up and carried by bloodstream
purely endocrine system organs
pituitary, thyroid, parathyroid, adrenal, and pineal glands
define “hormon”
urge on
what are hormones?
chemical messengers that act on organs and normally regulate growth, reproduction, and metabolism
How long do hormones take to work?
Varies; some take seconds, minutes, or hours
how does the nervous system act?
By generating nerve impulses to activate or inhibit effector organs. Sometimes stimulates release of hormones.
How long do nerve impulses last?
effect in milliseconds, result short-lived
what do nerve impulses normally cause?
muscle contraction and secretion of fluids from certain glands
what glands are located in the brain
the hypothalamus, pituitary gland, and pineal gland
what glands are in the neck?
thyroid gland with four parathyroid glands behind it
what gland is in the chest?
thymus
what glands lie on top of the kidneys?
adrenal (suprarenal) glands
what lets cells pick what hormones they need
receptors (glycoproteins)
what happens when there is an excess of hormones?
number of receptors decrease
define “para”
near
define “auto”
self
where do paracrine hormones act?
cells right next to it without crossing the bloodstream
where do autocrine cells act?
on the cell that secreted them. Cancer cells love these.
where does the pituitary gland lie
sella turcica (“Turkish saddle”) at base of the brain, behind the optic chiasm
what controls the pituitary gland?
hypothalamus
