Renal System Practice Cards Flashcards
How many stages are there of chronic kidney disease?
5
What organs make up the urinary system?
kidneys, ureters, bladder and urethra
what removes metabolic wastes?
the kidneys
What type of function is the regulation of red blood cell production?
renal function
What is the basic functional unit of a kidney?
A nephron
what is the glomerulus part of?
the renal corpuscle
What are peritubular capillaries branches of?
the efferent arteriole
What nephrons are there?
cortical and juxtamedullary
how many nephrons are there approx. per kidney?
1 million
What is the site of blood filtration?
the renal corpuscle
is filtration at the renal corpuscle active or passive?
passive
Should you ever see proteins in healthy urine?
No
Where does filtrate enter?
the proximal convoluted tubule
Does reabsorption occur at the proximal convoluted tubule?
Yes
What are the limbs of the nephron loop called?
the ascending and descending limb
What limb pumps sodium and chloride ions out of the tubular fluid?
the thick descending limb
What limb creates a high solute concentration in the peritubular fluid?
the thick ascending limb
What tubule has selective reabsorption under hormonal control?
The distal convoluted tubule
What is the juxtaglomerular complex made up of?
macula densa + juxtaglomerular cells
What does the juxtaglomerular complex secrete?
renin + EPO
What is the role of the collecting duct?
delivery of urine and variable reabsorption of water
what are the basic processes of urine formation?
filtration, reabsorption and secretion
Should glucose be found in a healthy person’s urine?
No
What involves a passage across a filtration membrane?
glomerular filtration
What are the forces determining filtration pressure?
GHP, CsHP and BCOP
GHP
glomerular hydrostatic pressure
CsHP
capsular hydrostatic pressure
BCOP
blood colloid osmotic pressure
What is the glomerular filtration rate?
the amount of filtrate the kidneys produce each minute (GFR) (avg. 125mL/min)
What are the controllers of glomerular filtration rate (GFR) ?
regulation/ autoregulation/ hormonal
What is the myogenic mechanism?
- an increase in renal blood flow or blood pressure eg running. = vasoconstriction
- a decrease in blood flow > decreased glomerular pressure eg lying down –> dilation of afferent/ constriction of efferent
Autoregulation of GFR is…
immediate local regulation
Extrinsic regulation of GFR…
mainly responds to stressful situations
Autonomic regulation of GFR…
increased sympathetic activity -> vasoconstriction of afferent arterioles
Hormonal regulation of GFR…
renin-angiotensin system + naturetic peptides
What cells secrete renin?
granular cells
Where is aldosterone produced?
in the adrenal cortex of the adrenal glands
Where and when are natriuretic peptides released?
In the heart and in response to a large increase in blood pressure
Do natriuretic peptides increase urine production?
Yes (dilate afferent and constrict efferent)
What percentage of sodium and water is resorbed at the proximal convoluted tubule?
65%
What does secondary linked reabsorption mean?
means that sodium travels via active transport and glucose joins onto it and travels passively
What is the renal threshold?
the concentration of a substance dissolved in the blood above which the kidneys begin to excrete it into the urine
What does water reabsorption at the proximal convoluted tubule occur via?
osmosis
At the nephron loop what percentage of sodium is reabsorbed?
25%
At the nephron loop what percentage of water is reabsorbed?
15%
Why is the reabsorption percentage for sodium and water different at the nephron loop?
different values as one is ascending and the other is the descending loop
What is tee only limb that water reabsorption occurs in?
The thin descending limb
What removes water leaving the loop of henle?
blood in the vasa recta
What percentage of sodium is reabsorbed in the distal convoluted tubule?
9%
What percentage of water is reabsorbed in the distal convoluted tubule?
19%
Where is anti-diruretic hormone made?
the hypthalamus
What triggers osmoreceptors?
an increase in ECF concentration
What is rapidly adjusted by ADH?
ECF concentration
What is ECF volume slowly adjusted by?
aldosterone
what pH does acidosis occur at?
<7.35
What pH does alkalosis occur at?
> 7.45
Where is bicarbonate freely filtered?
the glomerulus
What do the kidneys do when the plasma pH is low? (H+ high)
the kidneys secrete alot of H+
What do the kidney do when the plasma pH is high? (H+ low)
the kidneys secrete less H+
What type of acid-base disorders are there?
respiratory or metabolic
What acid base disorders involve production of organic or fixed acids?
metabolic acid base disorders
What is an example of respiratory acidosis?
emphysema
