A&P final Flashcards
What percent of PAH is removed from the blood as it passes through the kidneys?
90%
Despite the fact that angiotensin II would constrict the afferent arteriole by itself, the afferent arteriole will actually relax d/t
the effect of Nitric oxide mediated relaxation being the stronger force
If you vasodilate both the efferent and afferent arteriole you would expect ______ blood flow and ________ filtration
increased blood flow
decreased pressure d/t efferent constriction and increased pressure d/t afferent constriction could lead to possibly no difference in filtration.
Angiotensin II type 1 receptors are found in the _______ and respond to____.
What is the result of this?
in the PCT
angiotensin II
increases the rate of the Na+/K+ pump which therefore increases other pumps that rely on it.
Na+/K+ pump primarily speeds up which pump in the PCT?
secondarily speeds up?
Na+ Hydrogen Exchanger
The reabsorption process for bicarb via the Na+/HCO3- pump. This is done because of the Na+/H+ (Na+ Hydrogen) pumping out Hydrogen and making the cell more negative. This should push HCO3- out of the cell.
slide 14 pic
What kind of transporter is the Na+/HCO3- pumps?
Symporter
secondary active transporter
What is the primary driver for the Na+/HCO3- pump?
HCO3-
Some texts say that the Angiotensin II type 1 receptors directly effects which pumps?
the Na+/K+ pump (has a lot of science to back this)
the Na+/HCO3- pump (Smidt says this is possible but not as much science to prove it so probably relies more on the Na+/H+ pump)
How does the Na+/K+ pump effect the Na+/HCO3-pump?
if affects the Na+/H+ pump
proton leaving makes HCO3-want to leave
Pathway between the cells are called______. In the PCT these spaces are wide or narrow?
What is it called when something is reabsorbed through this route?
tight junction
Wide
Paracellular reabsorption
What is transcellular reabsorption?
When a substance moves through a transporter or channel in the cell wall
Through which pathway does a lot of substances get “dragged”?
paracellular route
d/t a massive amount of fluid flowing between cells
What is the most common ion that gets “dragged” through the cells via paracellular reabsorption in the PCT?
Why is this?
Cl-
Because there is a lot of movement of Na+ and where a positively charged Na+ goes, Cl- likes to follow
What is the transcellular route for water called?
aquaporin
The places in the kidney that are impermeable to water have what kind of tight junctions? Are there aquaporins in these areas?
very tight junctions
They probably don’t have aquaporins in them either
what is bulk flow?
reabsorption d/t the pushing and pulling forces that are in the capillaries and ISF.
10mmHg in the peritubular capillaries
Are there water pumps in the body?
No! The only pump we don’t have. Water moves via osmosis
what is urea?
A waste product that the body uses to help create a concentrated renal ISF so that we reabsorb water via osmosis
If we are in the desert for a couple of days, what is our urine going to look like and why?
Very concentrated! The body creates more urea to increase reabsorption of water so that the body is conserving water.
The transcellular path is driven by what kind of diffusion?
active diffusion
Passive diffusion is driven by what kind of diffusion?
passive diffusion
What is the purpose of the brush boarder on the lumanal side of the tubule and where is it really prevalent at?
Increase surface area by 20X to put more transporters on the cell wall.
PCT
The cells in the kidney has a resting membrane potential of_____.
This helps us to pull in which ion?
-70mV
Na+
Na+ is pulled into the cells in the kidney via what kind of gradient?
electrochemical gradient
part of the driving force for our secondary active transporters.