Urinary 2

Question 1

Renal corpuscle

Answer 1

Filters blood plasma
Glomerulus - capillary network
Glomumerular capsule - double walled cup surrounds glomerulus

Question 2

renal tubule

Answer 2

proximal convoluted tubule
loop of henle -1 .thin descending limb and 2. ascending limb with thin and thick segments
distal convoluted tubule

Question 3

fenestration of glomerular endothelial cell

Answer 3

prevents filtration of blood cells but allows all components of blood plasma to pass through

Question 4

basal lamina of glomerulus

Answer 4

prevents filtration of larger proteins

Question 5

slit membrane between pedicels

Answer 5

prevents filtration of medium sized proteins

Question 6

flow of fluid thrpugh a juxtamedullary nephron

Answer 6

glomerular capsule 
proximal convoluted tubule 
descending limb of the nephron tuble 
ascending limb .... 
distal convoluted tubule (which drains into collecting duct )

Question 7

what layers are in the glomerular capsule

Answer 7

visceral and parietal

Question 8

visceral layer of glomerular capsule

Answer 8

consists of modified simple squamous epithelial cells called podocytes

Question 9

parietal layer glomerular capsule

Answer 9

simple squamous epithelium

outer wall of capsule

Question 10

where is the fluid filtered from the glomerular capillaries

Answer 10

the fluid enters capsular space ,the space btw the two layers of glomerular capsule ,which is continuous with the lumen of the renal tubule

Question 11

cells in the proximal convoluted tubule

Answer 11

simple cuboidal epithelial cells with a prominent brush border of microvilli on their apical surface

Question 12

cells in the descending limb and thin ascending limb of nephron limb

Answer 12

simple squamous epithelium

Question 13

thick ascending limb of nephron loop is composed of what cells

Answer 13

simple cuboidal to low columnar epithelium

Question 14

what two cells are in the DCT and continuing into the collecting ducts

Answer 14

principal cells that have receptors for both antidiuretic hormone and aldosterone
intercalated cells which play a role in homeostasis of blood pH

Question 15

What does the JGA help with

Answer 15

regulate blood pressure inside the kidneys

Question 16

macula densa

Answer 16

specialized cells lining the wall of the distal tubule ,at the point where the thick ascending limb meets the distal convulated tubule

Question 17

juxtaglomerular cells

Answer 17

modified smooth muscle fibers found in the walls of afferent and efferent arterioles

Question 18

glomerular filtration

Answer 18

in the first step of urine production ,water and most solutes in are filtered and move into the glomerular capsule

Question 19

tubular reabsorption

Answer 19

as filtered fluid flows through the renal tubules and through the collecting ducts ,tubule cells reabsorb about 99% of the filtered water and many useful solutes

Question 20

tubular secretion

Answer 20

as filtered fluid flows through the renal tubules and collecting ducts ,the renal tubule and duct cells secrete other materials ,such as wastes ,drugs and excess

Question 21

filtration membrane

Answer 21

endothelial cells of glomerular capillaries and podocytes encircling capillaries.It permits filtration filtration of water and small solutes .prevents filtration of most plasma proteins ,blood cells and platelets

Question 22

3 barriers to cross in the filtration membrane

Answer 22

glomerular endothelial cells fenestration’s ,basal lamina btw endothelium and podocytes and pedicels of podocytes create filtration slits

Question 23

why is the volume of fluid filtered large ?

Answer 23

large surface area
thin and porous membrane
high glomerular capillary BP

Question 24

Glomerular filtration rate

Answer 24

the amount of filtrate formed in all renal corpuscles of both kidneys each minute
male 125 mL/min
female 105 mL/min

Question 25

what three mechanisms regulate GFR

Answer 25

renal auto regulation neural regulation hormonal regulation

Question 26

myogenic mechanism

Answer 26

occurs when stretching triggers contraction of smooth muscle cells in afferent arterioles -reduces GFR

Question 27

tubuloglomerular mechanism

Answer 27

macula densa provides feedback to glomerulus ,inhibits release of NO from cells in the JGA ,causing afferent arterioles to constrict and decreasing GFR (slower than myogenic mechanism )

Question 28

neural regulation

Answer 28

kidney blood vessels supplied by sympathetic ANS fibers that release norepinephrine causing vasoconstriction moderate stimulation -both afferent and efferent arterioles constrict to same degree and GFR decreases slightly greater stimulation - constriction of afferent arterioles predominates blood flow into the glomerular capillaries is greatly decreased and GFR drops

Question 29

hormonal regulation

Answer 29

angiotension II reduces GFR (potent vasoconstrictor ) atrial natriuretic peptide increases GFR - stretching of atria causes ANP release ,ANP causes relaxation of intra-glomerular mesangial cells increases capillary surface area for filtration

Question 30

net filtration depends on what pressures

Answer 30

glomerular blood hydrostatic pressure capsular hydrostatic pressure blood colloid osmotic pressure

Question 31

capsular hydrostatic pressure

Answer 31

pressure exerted against the filtration membrane by fluid in the capsular space and renal tubule

Question 32

glomerular blood hydrostatic pressure

Answer 32

BP in the glomerular capillaries

Question 33

blood colloid osmotic pressure

Answer 33

due to the presence of proteins in blood plasma

Question 34

net filtration pressure formula

Answer 34

NFP=GBHP-CHP-BCOP

Question 35

Reabsorption

Answer 35

return of most filtered fluid and substrate from the tubular lumen to the peritubular capillaries

Question 36

secretion

Answer 36

from the peritubular capillaries to the tubular lumen

Question 37

paracellular re-absorption

Answer 37

fluid can leak between the cells in a passive process in proximal convoluted tubules

Question 38

trans-cellular re-absorption

Answer 38

substances passes from the tubular lumen through the apical membrane of a tubule cell ,across the cytosol and out into interstitial fluid through the basolateral membrane

Question 39

primary active transport

Answer 39

energy derived from hydrolysis of ATP is used to pump a substance across a membrane

Question 40

secondary active transport

Answer 40

energy stored in an ions electrochemical gradient ,rather than hydrolysis of ATP ,drives another substance across a membrane

Question 41

symporters

Answer 41

are membrane proteins that move two or more substances i the same direction across a membrane

Question 42

antiporters

Answer 42

move two or more substances in the opposite directions across the membrane

Question 43

oobligatory water reabsorption

Answer 43

water reabsorbed with solutes in tubular fluid because water is obliged to follow solutes when they are reabsorbed (occurs in convulated tubule and descending limb of the nephron loop )

Question 44

faculatative water reabsorption

Answer 44

re-absorption of the final 10 percent of water regulated by - anti-diuretic hormone occurs in collecting ducts

Question 45

reabsorption in the proximal tubule

Answer 45

65 % of filtered water ,sodium and pottasium reabsorbed 100 % of most filtered organic solutes 80% of filtered bicarbonate

Question 46

reabsorption of loop henle

Answer 46

reabsorption of glucose ,amino acids ,other nutrients ,water and solutes balanced 15% filtered water 20-30% filtered sodium and potassium

Question 47

why is the reabsorption of water NOT coupled automatically to reabsorbtion of solutes

Answer 47

part of the loop of henle is relatively impermeable to water

Question 48

how much water is absorbed in the ascending limb

Answer 48

none ,because osmolarity progressively decreases as fluid moves towards end of ascending limb

Question 49

what does the early distal convoluted tubule do

Answer 49

reabsorbs 10%-15% of the filtered water ,the major site where parathyroid hormone stimulates reabsorption of Ca+ depending on bodys needs

Question 50

reabsorption and secretion in the late distal convoluted tubule and collecting duct

Answer 50

90-95% have been returned by now principal cells reabsorb Na + and screte K+ intercalated cells reabsorb K+ and HCO3-