Physiology 3

Question 1

the basal lamina is the same as the basement membrane of the capillary: T or F

Answer 1

T

Question 2

gaps between podocytes are called…

Answer 2

filtration slits

Question 3

the basement membrane is made up of what 2 structures?

Answer 3

collagen

glycoproteins

Question 4

why does the basement membrane repel plasma proteins?

Answer 4

it is negatively charged and thus will repel negative plasma proteins

Question 5

name the 3 filtration barriers of the glomerulus

Answer 5

glomerular capillary endothelium
basement membrane
filtration slits

Question 6

name the 3 layers that make up the glomerular membrane (inner to outer)

Answer 6

endothelial cells in lumen
basement membrane
filtration slits

Question 7

the pressure of blood in the capillary is known as?

Answer 7

glomerular capillary BP

Question 8

biggest determinant of net filtration pressure?

Answer 8

glomerular capillary BP

Question 9

blood pressure is constant in the glomerular capillary T or F

Answer 9

T

Question 10

“oncotic” should make you think…

Answer 10

plasma proteins

Question 11

name the 4 forces that determine the net filtration pressure

Answer 11

glomerular capillary BP
bowmans capsule hydrostatic pressure
bowman’s capsule oncotic pressure
capillary oncotic pressure

Question 12

what does the capillary oncotic pressure do?

Answer 12

tries to attract fluid from bowman’s capsule into lumen of capillary

Question 13

why is bowman’s capsule oncotic pressure negative?

Answer 13

no plasma proteins formed in tubular fluid of bowman’s capsule

Question 14

how do you work out the net filtration pressure?

Answer 14

(GCBP + BCOP) - (COP + BCHP)

Question 15

normal net filtration pressure?

Answer 15

10mmHg

Question 16

main determinant of GFR?

Answer 16

GCBP

Question 17

normal GFR?

Answer 17

125ml/min

Question 18

what controls extrinsic regulation of GFR?

Answer 18

sympathetic control via baroreceptor reflex

Question 19

if blood pressure in the glomerulus is increased, what would happen to the GFR?

Answer 19

it would increase too

Question 20

how can the glomerulus control how much blood flows through it?

Answer 20

it can alter the diameter of the afferent arteriole

Question 21

how does sympathetic control reduce GFR?

Answer 21

causes vasoconstriction of blood vessels so will constrict the afferent arteriole

Question 22

MABP is?

Answer 22

93mmHg

Question 23

increased GFR will increase or decrease the amount of salt in the tubular fluid?

Answer 23

increase

Question 24

what do macula densa cells do when they sense salt in the tubular fluid?

Answer 24

release vasoconstrictive substances to bring GFR back to normal

Question 25

what effect would a kidney stone have on GFR and how?

Answer 25

would decrease it by increasing bowman's capsule fluid pressure

Question 26

burns have what effect on GFR?

Answer 26

increase it

Question 27

what is plasma clearance?

Answer 27

the volume of plasma cleared of a particular substance per minute

Question 28

what kind of substance is inulin (NOT insulin)?

Answer 28

polysaccharide

Question 29

inulin clearance = GFR T or F

Answer 29

T

Question 30

how does inulin enter the urine?

Answer 30

filtration only (not by secretion or reabsorption)

Question 31

where is the main area of filtration in the kidney?

Answer 31

glomerulus

Question 32

clearance of urea is less than the GFR T or F

Answer 32

T

Question 33

a substance is said to be reabsorbed if clearance is more/less/equal to/than the GFR?

Answer 33

less

Question 34

a substance is said to be neither reabsorbed nor secreted if clearance is more/less/equal to/than the GFR?

Answer 34

equal to

Question 35

a substance is said to be secreted into the tubule if clearance is more/less/equal to/than the GFR

Answer 35

more

Question 36

best way to estimate GFR?

Answer 36

creatinine