Excretatory System Flashcards
what is the renal corpuscle
pat of the nephron that carries out the initial filtration located in the renal cortex
contains glomerulus and Bowmans capsule
describe the path of urine out the body
renal corpuscle renal tubule collecting duct medullary pyramid renal pelvis ureter urinary bladder urethra
what is the renal tubule
portion responsible for adjusting volume and concentration of the urine
contains the proximal and distal convoluted tubule and the loop of henle
what happens at the PCT
absorption of sodium , glucose, vitamins, amino acids
whats the purpose of the loop of henle
reduce the volume of the filtrate without changing the concentration
what happens in the descending limb
permeable to water not ions so as you go down into the concentrated medulla waters flows out and back into circulation
what happens in the ascending limb
impermeable to water
Na and K diffuse down the concentration gradient
at the top part ACTIVE transport of these ions
why is the loop of henle knowns as the countercurrent multiplier
blood is removed by the vasa recta which allows the medulla to stay concentrated and the cortex to stay less concentrated so the concentration gradients stay
what does aldosterone do
acts on DCT and collecting duct to increase sodium absorption therefore increasing water absorption
increases blood pressure
what does ADH/vasopressin do
increases water absorption in the collecting duct
increases blood pressure
what does ANP do
promotes sodium retention in the urine
decreases the blood pressure
what stimulates the RAAS system
juxtaglomerular cells in the arterioles of kidneys release renin in response to low blood pressure, reduced sodium, or sympathetic system
the path of the RAAS system
renin converts angiotensinogen into angiotensin
ACE converts angiotensin 1 into 2
stimulates the brain to release ADH and the adrenal cortex to release aldosterone
functions of the kidney
regulate blood pressure, pH
excretion of nitrogenous waste (urea)
