Homeostasis Test Flashcards
Where is the pituitary gland located?
Base of the brain
What is the function of the pituitary gland
secrete hormones or make other glands secrete hormones
where is the thyroid gland located
in the neck
what is the function of the thyroid gland
to secrete T4and T3
What do T4 and T3 do
regulate body temp, metabolism and energy levels
where is the parathyroid gland located
behind the thyroid gland in the neck
what is the function of the parathyroid gland
regulate calcium levels
how does the parathyroid gland regulate calcium levels
secretes PTH which releases calcium from bones and tells excretory system to absorb more calcium
What are two ways to increase blood pressure
Angiotensin: decrese the diameter of blood vessels
Aldosterone: increases the amount of fluid flowing into blood vessels by increasing NA+ concentration in blood
what is hypertension
high blood pressure
why is hypertention (high blood pressure) a health risk
it can strain organs and lead to their failure
what cells monitor blood pressure
juxtaglomerular receptor cells
what hormone regulates water balance in blood
anti diruretic hormone
where is ADH produced
hypothalamus
where is adh stored
pituitary gland
what cells are responsible for the secretion of adh
osmoregulator cells
when is adh secreted
high osmotic pressure
high solute conc. in blood
dehydrated
when is adh not secreted
low osmotic pressure
low solute conc. in blood
hydrated
what does the body do when there is high osmotic pressure
adh is secreted from the pituitary gland, it binds to receptors on the distal convoluted tubule and the collecting duct, this openes up aquaporins which reabsorb more water
is filtration nephron into blood or blood into nephron
blood into nephron
is reabsorption blood into nephron or nephron into blood
nephron into blood
is secretion blood into nephron or nephron into blood
blood into nephron
after the fluid is pushed from glomerulus into bowmans capsule what is it then called
primary urine
what does primary urone contain
glucose, salt, urea, AA
what cells line the proximal convoluted tubule
endothelial cells
does active or passive transport happen first in the PCT
active
what happens during active transport in the PCT
Na/K pumps in the endothelial cells pump Na out of the primary urine and back into the blood.
Since active transport in the PCT cant work by itself, what powers it
ATP
what does the Na/K pump create in the nephron
conc. gradient
what happens during passive transport in the PCT
Cl anions follow the Na ions out of the nephron because of charge attraction.
water, glucose and AA follow the conc. gradient and go back into the bloodstream
what happens in the descending limb of the loop of henle
its permeable to water but not Na. Its saltier outside the limb so water flows out causing conc. urine
what the conc. of the urine at the bottom of the loop of henle
1200
what happens in the ascending limb of the loop of henle
its permeable to Na but not water. Na leaves the limb with Cl ions following it. (charge attraction) the urine is less conc.
what happens in the DCT
it fine tunes the urine, reabsorbing any other water or electrolytes the blood needs
what happens in the collecting duct
most of the remaining water in the urine is absorbed creating conc. uring
what happens after the urine passes through the collecting duct
it goes to the renal pelvis
what happens after urine goes to the renal pelvis
it goes down the ureters and collects in the bladder for storage
what organisms match the osmolarity of their environment
osmoconformers (squid)
what organisms have a consant osmolarity despite their external environment
osmoregulators (humans)
what does a negative feedback loop do
start, end, repeat.
activated when needed
what does a positive feedback loop do
start, end, repeat until process is done.
give an example of a positive feedback loop
childbirth
give an example of a negative feedback loop
insulin/glucagon or body temp
how are the nervous and endocrine systems different
endocrine: releases hormones that are slower acting but longer lasting
Nervous: electrical signals that act almost immidiately
what are the different classifications of hormones
peptide, steroid, amino acid, fatty acid
example of a peptide hormone
FSH, LH, oxytocin
example of a steroid hormone
testosterone, estrogen, progesterone
example of an AA hormone
epinephrine, norepinephrine
