renal physiology Flashcards
which nephron structure is especially important in the kidneys ability to produce urine of varying concentration
loop of henle
how is glomerular filtrate formed
as a result of passive forces acting across the glomerular membrane
what does a large increase in blood colloid osmotic pressure do to the net filtration pressure
it reduces it
what does afferent arteriolar vasoconstriction do to the blood flow in the glomerulus
decreases it
what does afferent arteriolar vasoconstriction do to the GFR
decreases it
When arterial blood pressure is elevated above normal, which compensatory changes in renal function occur as a result of the baroreceptor reflex
afferent arteriolar vasodilation
what is renal threshold
plasma concentration of a particular substance at which its Tm is reached and the substance first appears in the urine
what does aldosterone do
stimulates Na+ reabsorption in the distal and collecting tubules and stimulates K+ secretion in the distal tubule
how is angiotensin I formed
as a result of activation of angiotensinogen by renin, and is transformed into angiotensin II as a result of converting enzyme action in the lungs
what part of the juxtamedullary nephron establishes the medullary vertical osmotic gradient by means of countercurrent multiplication
loops of henle
what does vasopressin do
activates the cyclic AMP second messenger system within the tubular cells
what segment of the nephron is not permeable to H2O even in the presence of vasopressin
ascending limb of the loop of henle
how does urine move from the kidneys to the urinary bladder through the ureters
by peristaltic contraction of the smooth muscle of the ureters
