Renal Physiology (Don's Class) Flashcards
Body can drop _____ % GFR before serious problems.
20%
Production of _____ begins with ______ and ______ filtration from the plasma flowing into the glomerulus via the _______ arteriole.
-urine
-water and solute
-afferent
Role of the Glomerulus is to form an _______ of _________.
ultra filtrate of plasma
It is the ______ _______ of the _______ arteriole which plays a large role in the flow through the glomerulus.
muscle tone
afferent
Basement membrane is _______ charged due to ___________ which compose it.
negatively
glycoproteins
-Negatively charged proteins are thus repelled and are unable to pass through it.
The basement membrane effectively prevents filtration of _______ _______, in part because of strong ________ electrical charges associated with the proteoglycans.
plasma proteins
negative
GFR is defined as total volume per unit time (ml/min) which leaves the ________ and enters __________ ________.
capillaries
Bowmans space
The two major determinants of filtration pressure are ________ _______ _______ and _____ ______ ______.
glomerular capillary pressure (PGC)
glomerular oncotic pressure (pgc).
GFR is around ____ml/min which is around _____ L/day
120 ml/min
180 L/day
Glomerular capillary pressure is directly related to __________ and is heavily influenced by _____ _____ at points upstream (______) and downstream(_________) from the glomerulus
-renal artery pressure
-arteriol tone
-afferent
-efferent
Renal blood flow is around ____% of cardiac output. (_______ml/min)
20%
1200
4 factors that determine GFR.
- Ultrafiltration coefficient
- Oncotic Pressure
- Capillary Pressure
- Plama Flow Rate
Capillary plasma flow rate: Higher flow =
greater filtration
How does the body get back filtered plasma?
As the plasma moves towards the end of the glomerular capillary, filtration ________ because of an increase in _______ _______ (as fluid is removed the protein concentration ________)
-slows
-oncotic pressure
-increases
This term reflects the kidney’s ability to regulate GFR over a range of conditions
Autoregulation
The ______ ______is a specialized group of epithelial cells in the ________ tubules that comes in close contact with the afferent and efferent arterioles
-macula densa
-distal
The macula densa cells contain ________ ________, which are intracellular secretory organelles directed toward the arterioles, suggesting that these cells may be secreting a substance toward the arterioles.
Golgi Apparatus
Decrease in sodium chloride concentration initiates a signal from the macula densa that has two effects:
(1) It decreases resistance to blood flow in the afferent arterioles, which raises glomerular hydrostatic pressure and helps return GFR toward normal.
(2) It increases renin release from the juxtaglomerular cells of the afferent and efferent arterioles, which are the major storage sites for renin.
Tubular __________ is quantitatively more important than tubular _________in the formation of _____, but _________plays an important role in determining the amounts of _______ and _______ ions and a few other substances that are excreted in the urine.
-reabsorption
-secretion
-urine
-secretion
-potassium
-hydrogen
Defined as the volume of plasma from which all of a given substance is removed per unit time in one pass through the kidney.
Renal Clearance
If a substance is neither secreted nor reabsorbed, then its clearance is ______to GFR (e.g., ______)
-equal
ex. insulin
If a substance is completely reabsorbed, then clearance is ______(e.g., _______ under normal cond.)
-zero
-ex. glucose
If Cx > GFR there must be net ______.
secretion
If Cx < GFR there must be net _______.
reabsorption
If Cx = GFR there is neither…..
net reabsorbtion or net secretion
Normal Renal Function and GFR
100% functioning nephrons
GFR 125 ml/min
Reduced Renal function and GFR
10-40% functioning nephrons
GFR 12-80 ml/min
Renal Failure , function and GFR
<10 % functioning nephrons
GFR <12 ml/min