Renal Day 2

Question 1

what are macula densa cells?

Answer 1

cells that detect content of tubular fluid to know what to pass through (on distal convoluted tubule that sits next to afferent arteriole)

Question 2

what are mesangial cells?

Answer 2

border glomerulus and function as precapillary sphinters to control pressure through glomerulus

Question 3

what is the tubular pole?

Answer 3

where proxima convoluted tubule emerges off bowman’s capusel

Question 4

what are podocytes?

Answer 4

filtration slits that sit outside the fenestrated glomerulus

Question 5

what type of cells makes up the tubules of a nephron?

Answer 5

simple cuboidal with microvilli

Question 6

what type of cells make up the loop of Henle?

Answer 6

simple squamous

Question 7

what is normal plasma osmolarity?

Answer 7

300

Question 8

where does most of reabsorption occur?

Answer 8

proximal convoluted tubule

Question 9

what happens to tubular fluid osmolality as it passes through the loop of Henle?

Answer 9

1. descending osmolality increases
2. ascending osmolality decreases and becomes hypoosmotic
3. collecting duct urine is dilute and has low osmolality

Question 10

what is the normal urine output per day?

Answer 10

1-2L

Question 11

which leg of the loop of Henle is immpermeable to water?

Answer 11

ascending limb

Question 12

which leg of the loop of Henle is not permeable to solutes?

Answer 12

descending loop

Question 13

where are principle cells located?

Answer 13

distal convoluted tubule and collecting duct

-use aldosterone and ADH to reabsorb more water

Question 14

what are intercalated cells?

Answer 14

they control and monitor pH by secretion of hydrogen and potassium into the tubular fluid
located at distal end of DCT

Question 15

where are the two places that contain transitional epithelum?

Answer 15

ureters

bladder

Question 16

what is the triangular area in the bladder?

Answer 16

trigone

ureteral openings and neck of urinary bladder

Question 17

is there a true sphincter in the bladder?

Answer 17

no (contains a physiologic valve)

-ureteral reflux

Question 18

how many layers does the detrusor muscle have?

Answer 18

3 layers of smooth muscle (not skeletal)

Question 19

what is a risk factor for bladder infection?

Answer 19

stasis (urine staying in the bladder)

age causes weakening of muscles

Question 20

what is an intravenous pyelogram?

Answer 20

way to visualize the urinary system

Question 21

what is the rate of secretion?

Answer 21

(glomerular filtration + tubular secretion) - tubular reabsorption

Question 22

how much filtrate is produced each day?

Answer 22

150L f

180L m

Question 23

what is the net filtration pressure at the glomerulus?

Answer 23

10mmHg

Question 24

what is the hydrostatic pressure at the glomerulus?

Answer 24

55mmHg

Question 25

what is the relationship between mesangial cells and filtration rate?

Answer 25

relaxed cell = higher rate | contracted cell = lower rate

Question 26

what is the definition of GFR?

Answer 26

amt of filtrate formed in all the nephrons in both kidneys each minute

Question 27

what happens when GFR is too high?

Answer 27

reabsorbed materials aren't sufficient

Question 28

what happens when GFR is too low?

Answer 28

reabsorbed materials will include some waste

Question 29

when will filtration halt?

Answer 29

when hydrostatic pressure drops below 45mmHg | -when not enough perfusion is coming in

Question 30

what is the lower and upper threshold of MAP at which GFR would change?

Answer 30

80-180mmHg

Question 31

what are the 4 ways in which the kidney autoregulates?

Answer 31

1. myogenic (works w/in seconds) 2. tubuloglomerular feedback 3. neural feedback 4. hormonal feedback

Question 32

if systemic blood pressure is higher, what happens in the kidney?

Answer 32

flow of fluid in the tubular system is faster | macula densa inhibits NO which vasoconstricts afferent arteriole

Question 33

how does sympathetic input impact glomerular?

Answer 33

GFR is decreased b/c afferent constricts more than the efferent -shunting of blood , shock b/c of hemorrhage, dehydration or stress

Question 34

when does the body make atrial natriuretic peptide?

Answer 34

hypervolemia | -diuresis the body

Question 35

what is paracellular reabsorption?

Answer 35

solutes move across to capillary in between cells

Question 36

what is transcellular reabsorption?

Answer 36

solutes move across to capillary going through the tubular epithelial cells

Question 37

what is a transport maximum?

Answer 37

depends on number of protein transporters and how fast they work -glucose threshold as example

Question 38

what is a aquaporin 2?

Answer 38

pure water channel (ADH related)