Renal Function Flashcards
What is the structure of the kidney from superficial to deep?
cortex–>medulla–>renal pelvis
What collects in the renal pelvis?
urine that is not futher modified once it reaches the renal pelvis
What is a nephron?
a “mini-kidney”
functional unit of the kidney
What 2 surfaces make up the epithelial cells?
the luminal surface, closest to the lumen,
sometimes called the apical surface!
- the basolateral surface, closest to capillaries in
interstitium!
What is the private blood supply of the nephron?
the afferent arteriole that forms tufts of capillaries called the glomerulus in Bowman’s capsule
How much of plasma filters out into Bowmans capsule?
about 20%
How does the remaining 80% exit the nephron?
by the efferent arteriole that can break into a capillary network surrounding the tubule called the peritubular capillary network
Where are the glomeruli found?
in the cortex of the kidney
Where do the collecting ducts run to empty?
they run through the medulla and empty into the renal pelvis
3 processes that the kidney performs to maintain homeostatis
filtration
reabsorption
secretion
What is tubular secretion?
this is an active process involving ATP by which the kidneys add solute to tubular fluid from the
peritubular capillary network
drugs and toxins are removed from the blood this way
What is tubular reabsorption?
this is the movement of water and solute from
tubular fluid back into peritubular capillaries!
• this is the major process of modification of
tubular fluid
dependent on active transport
uses energy to drive Na+/K+ ATPase
difference between systemic and renal capillaries
systemic capillaries filter 3-4 liters per day as
compared to renal capillaries at 180 liters per day!
renal capillaries also have a large hydrostatic pressure that remains high along the capillary
describe glomerular capillaries
they are leaky
everything that is in the capillary except cells and proteins can get out of
capillary into Bowman’s space
What happens to GFR if plasma creatinine is increasing?
GFR must be decreasing