Renal Function (Lect 2) Flashcards
Define tubular reabsorbtion
take materials out of urine and back into the blood stream (ex NA/H2O)
Define tubular secretion
atsbu
active transport secreted from blood into urine
What are the 4 parts of the urinary system and what do they do?
kidneys: urine is formed from filtrate
uteres: carries urine to bladder
bladder: stores urine
urethra: excretion
What are the primary functions of the kidney?
removal of waste products (nitrogenous)
Acid base balance
retention of essential nutrients
hormone production
water electrolyte balance
prod. of Vit D
What is the functional unit of the kidney? what does it do?
nephron, filters blood and creates urine reabs/excret
T/F there is 1-1.5 mil nephrons in each kidney
true
What are the two types of nephrons?
Cortical nephron (renal cortex)
(85%)
Juxtamedullary nephrons
long loops of henely
(inc urine concent)
Describe the Afferent pathway movement of urine
blood enters, golmerulous (first filter) - bowmans capsule, proximal tubule, henleys loop
Describe the Efferent pathway of exit
peritubular is the exit
Function of the kidney is controlled by?
b
gf
r/s
renal blood flow
golmerular filtrate
tubular reabsorption
tubular secretion
Briefly describe renal blood flow
renal artery supplies blood to kidney
25% of blood leaving left ventricle of heart enters the kidney
600mil/min renal plasma flow
What is similar in both the afferent and efferent pathway? what can they both do?
both change size/hydrostatic pressure
Describe the golmerulus
how many lobes
inside of
what kind of filter?
sizes?
permeablility?
8 capillary lobes
inside bowmans capsule
non-slective filter of plasma
less than 70,000 da
VERY PERMEABLE TO WATER
Describe the bowmans capsule
beninning of the renal tubular
bowmans space - capsule/golmerulous
Describe the tubules
re-absorption in proximal convuluted tubule
final adjustment in distal tubule
describe the loop of henley
what isnt in the ascending loop?
the major exchange of H2O/salt
no water reabsorp in acsending loop becuase it is impermeable
What are some factors that influence filtration?
cell wall structure
hydrostatic/oncotic pressure
RAAS
What are the three layers of the golmerulous
cw
b
v
(p/f)
capillary wall membrane
(fenstrated/permeability)
basement membrane
visceral epithelium
(podocytes,filter slit)
Describe what the shield of negativity does to the viceral epithelium layer of the golmerulous
repells anion plasma proteins
Describe hydrostatic pressure
pressure exerted by liquid increases filtration
Describe Oncotic pressure
pressure exerted by presence of unfiltered plasma…prescense of colloids
Describe hydrostatic pressure in more depth
based off?
due to?
fluncuations?
compensates with?
based of BP
due to the small size of efferent
fluncuations of blood pressure - affect hydrostatic pressure
compensate w autoregulatory
Describe Juxtagolmerulo function
Low BP?
maintains glomerulous blood pressure at constant rate
low BP =less blood flow = Inc toxic materials
dialates or constricts
Describe RAAS
changes in
reg by
changes in BP and plasma sodium, regulated by juxtagolmerulous (afferent/convoluted tubules detect salt)
Describe how RAAS would compensate for low sodium
less wr
lbv
dec
cells
less water retention
low blood vol
decreaseBP - signals Jux cells to release renin
Describe Angiotensin II
vasoconstriction
proximal convoluted tubules
Aldosterone/ADH
Describe Angiotensin I
lung and kidney
Describe Aldosterone
adrenal cortex
distal tubules
reabsorbtion of salt and water
Inc BP/BV
Describe ADH
h
inc
inc dp
c
inc
hypothalamus
inc water retention
inc distal tubule permeability
constrict blood vessles
inc BP
Final results of RAAS?
NA BP inc decreased prod of renin
T/F every minute, 120ml of low MW substances are tfiltered
true
How do you differentiate filtrate vs plasma
no plasma protein no protein bound substances
no rbc/wbc
Describe specific gravity post golmerulous
1.010 ultrafiltrate of plasma
T/F you reabsorb majority of water/salt from urine
true
Describe active transport
proximal tubule?
ascending loop
distal tube?
carrier protein, electrochemical energy
proximal tubule: glucose/amino/salt
Ascending loop: Cl-
Distal loop: Na+
Describe passive transport
concentration gradient/electrical potential gradients
T/F passive transport can be influenced by concn of substances being transported
false its active transport
Describe Max reabsorption capacity (Tm)
transport max
max absorbtion ability for solute in filtrate
Describe renal threshold
plasma concent at which active transport stops
glucose 160-180 high threshold
phosphate low threshold
T/F renal threshold and plasma {} are clinically useful
T
T/F normal people have glucose in thier urine
false
Describe renal concentration
starts
mech
final conc
lose
starts at loop of henly
osmotic gradients/concorrunt mechanism
final concentration ends at distal tubule/collecting duct
lose water in decending loop
Describe the countercurrent mechanism
pushes reabsorb of Na/H2O back to blood
Describe High ADH
incr perm
inc reab of H2O
dec urine vol/more concentrated
inc specific gravity
Describe Low ADH
dec perm
dec reab
inc urine vol/diluted
dec spec gravity
T/F hydrated has low ADH
Dehhydrated has High ADH
true
