Renal Physiology Exam With Complete
Questions and Answers 2024
Kidney receives what % of cardiac output? - ANSWER>>20-25%
What is the route of blood flow through the kidney? - ANSWER>>Renal artery ->
segmental artery -> interlobar artery -> arcuate artery -> interlobular artery -> afferent
arteriole ->glomerulus -> efferent arteriole -> peritubular capillaries (sometimes -> vasa
recta)
Constriction of afferent arteriole (increased resistance) causes - ANSWER>>Decreased
RBF, filtration pressure and GFR (decreased hydrostatic pressure in capillaries)
Constriction of efferent arteriole (increased resistance) causes - ANSWER>>Decreased
RBF, increased filtration pressure and GFR (increased hydrostatic pressure in
capillaries)
Dilation of afferent arteriole (decreased resistance) causes - ANSWER>>Increased
RBF, filtration pressure and GFR (increased flow and pressure with lower resistance)
Dilation of efferent arteriole (decreased resistance) causes - ANSWER>>Increased
RBF, decreased filtration pressure and GFR (maybe?)
Effect of NSAIDs on the kidney - ANSWER>>Block the production of prostagladins
(vasodilators) and promote constriction of the afferent arteriole
How would increased plasma protein concentration affect RPF, GFR and filtration
fraction? - ANSWER>>No change in RPF, decrease GFR and filtration fraction
What is the equation for filtration fraction? - ANSWER>>GFR/RPF
How is RPF calculated? - ANSWER>>RPF = (1-hematocrit) x RBF
How would decreased plasma protein concentration affect RPF, GFR and filtration
fraction? - ANSWER>>No change in RPF, increased GFR and filtration fraction
(Decreased oncotic pressure opposing filtration)
How would constriction of the ureter affect RPF, GFR and filtration fraction? -
ANSWER>>No change in RPF, decreased GFR and filtration fraction (increased
hydrostatic pressure opposing filtration)
Capillary lumen (in Bowman's capsule) lined with what sort of endothelium? -
ANSWER>>Fenestrated endothelium - relatively large to allow passage of solutes
, Glomerular basement membrane blocks what sort of molecules? - ANSWER>>Large,
negatively charged ones (feature of barrier = negatively charged glycoproteins)
Epithelial layer consists of - ANSWER>>Podocytes attached to basement membrane by
foot processes (hinders passage of big molecules)
What forces define the movement of fluid across capillary walls (glomerular filtration)? -
ANSWER>>Starling forces
Starling equation - ANSWER>>GFR = Kf [(Pgc - Pbc] - OPgc] OP = oncotic pressure
(or pi)
How would increased glomerular hydrostatic pressure affect GFR? -
ANSWER>>Increase GFR
What affects Kf, the filtration coefficient? - ANSWER>>Water permeability per unit of
surface area and the total surface area
How would increased pressure in Bowman's capsule affect GFR? -
ANSWER>>Decrease (think ureter dysfunction/blockage)
How would increased oncotic pressure affect GFR? - ANSWER>>Decrease (think
increased plasma protein concentration)
In glomerular capillaries, what happens to the oncotic pressure from beginning to end of
glomerulus? - ANSWER>>Increases due to increased amounts of plasma proteins (lost
its filtered water) but filtration pressure equilibriates at the end so there is no net
movement when becomes efferent capillary
What 3 factors would increase glomerular hydrostatic pressure? - ANSWER>>Efferent
arteriolar vasoconstriction, afferent arteriolar vasdilation and increase in RBF
What 2 factors would decrease glomerular hydrostatic pressure? - ANSWER>>Afferent
arteriole vasoconstriction and decrease in RBF
How would low levels of angiotensin II affect the filtration fraction? -
ANSWER>>Increase - efferent constriction = increased GFR (GFR/RPF)
What is the normal filtration fraction value? - ANSWER>>.2 or 20%
Howe would increased filtration fractions affect oncotic pressure? - ANSWER>>More
filtered = higher concentration of plasma proteins = higher oncotic pressure of
peritubular capillary blood
Where is the cortex of the kidney located? - ANSWER>>The outer region
Questions and Answers 2024
Kidney receives what % of cardiac output? - ANSWER>>20-25%
What is the route of blood flow through the kidney? - ANSWER>>Renal artery ->
segmental artery -> interlobar artery -> arcuate artery -> interlobular artery -> afferent
arteriole ->glomerulus -> efferent arteriole -> peritubular capillaries (sometimes -> vasa
recta)
Constriction of afferent arteriole (increased resistance) causes - ANSWER>>Decreased
RBF, filtration pressure and GFR (decreased hydrostatic pressure in capillaries)
Constriction of efferent arteriole (increased resistance) causes - ANSWER>>Decreased
RBF, increased filtration pressure and GFR (increased hydrostatic pressure in
capillaries)
Dilation of afferent arteriole (decreased resistance) causes - ANSWER>>Increased
RBF, filtration pressure and GFR (increased flow and pressure with lower resistance)
Dilation of efferent arteriole (decreased resistance) causes - ANSWER>>Increased
RBF, decreased filtration pressure and GFR (maybe?)
Effect of NSAIDs on the kidney - ANSWER>>Block the production of prostagladins
(vasodilators) and promote constriction of the afferent arteriole
How would increased plasma protein concentration affect RPF, GFR and filtration
fraction? - ANSWER>>No change in RPF, decrease GFR and filtration fraction
What is the equation for filtration fraction? - ANSWER>>GFR/RPF
How is RPF calculated? - ANSWER>>RPF = (1-hematocrit) x RBF
How would decreased plasma protein concentration affect RPF, GFR and filtration
fraction? - ANSWER>>No change in RPF, increased GFR and filtration fraction
(Decreased oncotic pressure opposing filtration)
How would constriction of the ureter affect RPF, GFR and filtration fraction? -
ANSWER>>No change in RPF, decreased GFR and filtration fraction (increased
hydrostatic pressure opposing filtration)
Capillary lumen (in Bowman's capsule) lined with what sort of endothelium? -
ANSWER>>Fenestrated endothelium - relatively large to allow passage of solutes
, Glomerular basement membrane blocks what sort of molecules? - ANSWER>>Large,
negatively charged ones (feature of barrier = negatively charged glycoproteins)
Epithelial layer consists of - ANSWER>>Podocytes attached to basement membrane by
foot processes (hinders passage of big molecules)
What forces define the movement of fluid across capillary walls (glomerular filtration)? -
ANSWER>>Starling forces
Starling equation - ANSWER>>GFR = Kf [(Pgc - Pbc] - OPgc] OP = oncotic pressure
(or pi)
How would increased glomerular hydrostatic pressure affect GFR? -
ANSWER>>Increase GFR
What affects Kf, the filtration coefficient? - ANSWER>>Water permeability per unit of
surface area and the total surface area
How would increased pressure in Bowman's capsule affect GFR? -
ANSWER>>Decrease (think ureter dysfunction/blockage)
How would increased oncotic pressure affect GFR? - ANSWER>>Decrease (think
increased plasma protein concentration)
In glomerular capillaries, what happens to the oncotic pressure from beginning to end of
glomerulus? - ANSWER>>Increases due to increased amounts of plasma proteins (lost
its filtered water) but filtration pressure equilibriates at the end so there is no net
movement when becomes efferent capillary
What 3 factors would increase glomerular hydrostatic pressure? - ANSWER>>Efferent
arteriolar vasoconstriction, afferent arteriolar vasdilation and increase in RBF
What 2 factors would decrease glomerular hydrostatic pressure? - ANSWER>>Afferent
arteriole vasoconstriction and decrease in RBF
How would low levels of angiotensin II affect the filtration fraction? -
ANSWER>>Increase - efferent constriction = increased GFR (GFR/RPF)
What is the normal filtration fraction value? - ANSWER>>.2 or 20%
Howe would increased filtration fractions affect oncotic pressure? - ANSWER>>More
filtered = higher concentration of plasma proteins = higher oncotic pressure of
peritubular capillary blood
Where is the cortex of the kidney located? - ANSWER>>The outer region
