renal function and kidney disease Flashcards
(28 cards)
functions of urinary system
filters waste products conserves nutrients regulates ion levels regulates blood pH regulate blood volume regulate erythrocyte production store/excrete urine secretes hormones
where are nephrons found
medullary regions
3 mechanisms of urine formation
glomerular filtration
tubular reabsorption
tubular secretion
what is glomerular filtration
filtering of blood into tubule forming primate urine
what is tubular resabsorption
absorption of substances needed by body from tubule to blood
what is tubular secretion
secretion of substance to be eliminated by the body into the tubule from blood
describe process of glomerular filtration
blood in the glomerulus within the bowman capsule
blood forced out under high pressure, protiens remain in the blood
what are the flitration forces
hydrostatic pressure of the blood entering (glomerular hydrostatic)
hydrostatic pressure within the capsule (capsular hydrostatic pressure)
blood colloid osmotic force
deserve the basement membrane
capitularies foot processes embedded in it
barrier with gaps in it
describe tubular resorption
filtrate moves to proximal tubule via passive/facilitated diffusion, primary active transport and secondary active transport
desrive AT in tubular resporbation
SGLT2 pumps sodium across the membrane- brings glucose
sodium is exchanged with potassium into blood (via AT)
glucose is transported by GLUT
what occurs at renal threshold
GLUT is saturated, no more glucose can diffuse in
describe tubular secretion
occurs in the proximal and distal tubule
maintains the acid/base balance and exchange of material
what hormones are used to maintain homeostasis
ADH
Renin-angiotensin system
what does RAAS do
stimulates sodium reabsorption in the distal tubules and collecting tubule
what is RAAS oppose by
natriuretic peptide
what is RAAS regulated by
kidney
what else can RAAS act on
aldosterone production in adrenal glands
what is aldosterone stimulated by
ANG II
potassium
fall in sodium
what regulates urine concentration
ADH/vasopressin
medullary counter current system
describe the use of vasopressin
hypothalamus detects change in osmolarity
increase in blood osmolarity - thirst repsonce
secretion of ADH by pituatory
increased permeability of collecting duct
how does ADH/vasopressin increase permeability of collecting duct
vesicles with aquaporins move to the membrane of the cell
how is an osmotic gradient established in the nephron
loop of henle
explain the meduallary counter current system
decending limb permeable to water, no AT of water
acending limb
impermable to water, AT sodium out of tubule
