Deck 52: Glomerular Filtration

Question 1

The filtra tion fra ctio n is

A) the ratio of glomerular filtration rate to renal blood flow
B) the ratio of glomerular filtration rate to renal plasma flow
C) the ratio of glomerular filtration rate to efferent arteriolar flow
D) the ratio of glomerular filtration rate to cardiac output
E) zero for large proteins

Answer 1

B

Question 2

During dehydration, glomerular filtration is reduced partly because the

A) Ultrafiltrate oncotic pressure Increases
B) Plasma hydraulic pressure Increases
C) Ultrafiltrate hydraulic pressure Increases
D) Plasma oncotic pressure Increases
E) Filtration coefficient Increases

Answer 2

D

Question 3

The GFR is best estimated by the clearance of

A) PAH
B) water
C) creatinine
D) inu lin
E) pho sph ate

Answer 3

D

Question 4

The m ajo r ba rrie r to filtra tion of p las m a p ro tein s s uc h a s a lbu m in is

A) endothelium
B) basement m embrane
C) pod ocyte slits
D) slit diaphragm
E) podocyte plasma mem brane

Question 5

In general, negative charges on proteins

A) Incre ase s the ir sieving coe fficien t towa rds 1.0
B) Inhibits filtration be cau se o f neg atively ch arge d so lutes in the u ltrafiltrate
C) Re du ces filtratio n b eca us e of neg ativ e ch arg es in the bas em en t m em bra ne and slit diaphragm
D) Has no effect on filtration at the glomerulus
E) Enhances filtration due to positive charges in the basement m embrane and slit diaphragm

Question 6

The units of clearance are

A) mL
B) M ole s m in-1
C) mL m in-1 / M
D) m L m in-1
E) Joules mol-1

Question 7

The m ajor barrier to filtration of red blood cells is the

A) endothelium
B) basement m embrane
C) pod ocyte slits
D) slit diaphragm
E) podocyte plasma mem brane

Question 8

The m ajor force favoring formation of the glomerular ultrafiltrate is the

A) Plasm a oncotic pressu re
B) Ultrafiltrate oncotic pressure
C) Plasm a hyd raulic p ressu re
D) Ultrafiltrate hydraulic pressu re
E) Hydraulic permeability of the glomerular mem brane

Question 9

The sie vin g c oe ffic ien t fo r pr ote ins de pe nd s o n th eir

A) size on ly
B) ch ar ge on ly
C) Both size and charge
D) den sity
E) diffusion coefficient

Question 10

Proteins with Stoke's radius > about 6 nm are excluded from the ultrafiltrate because

A) They are too large to fit through pores in the endothelium
B) They have too many negative charges and are repelled by the negative basement mem brane
C) T he y m ov e to o s low ly
D) They are too large to fit through pores in the s lit diaphragms
E) Th is is no t true. P rotein s with Stok es ra dius > 6 n m still end u p in the ultrafiltrate

Question 11

The clearance of PAH approximates the

A) Effective renal blood flow
B) GFR
C) Sieving coefficient
D) Effective renal plasma flow
E) Flow throu gh th e va sa re cta

Question 12

Urea has a molecular weight of 60. You would expect

A) the s ieving c oef ficient to be < < 1.0
B) its rate of filtration to be = GFR x U urea
C) its concentration in the ultrafiltrate to be the same as its concentration in plasma
D) its reflec tion co efficie nt to be 1.0
E) it to be secreted

Question 13

Which is NOT part of the reason why the clearance of inulin is equal to the GFR?

A) Inulin is freely filtered
B) Inulin is not reabsorbed
C) Inulin is not secreted
D) Inulin is not metabolized
E) Inulin crosses cell membranes

Question 14

The first evidence of the formation of a protein-free filtrate was provided by

A) Renal titration curves
B) M icro pu nc ture stu dies of th e glo m eru lar flu id
C) Microsc opic investigation of neph ron structure
D) Dem onstration that the potential obeys Gibbs-Donnan equilibrium
E) C alc ula tion of t he do ub le ra tio

Question 15

Blo od flow ing thr ou gh the eff er en t ar ter iole

A) Has the same concentration of small ions as afferent arteriolar blood but higher protein concentration
B) Is the same as blood everywhere else in the body
C) Is co nce ntrate d in all res pec ts du e to e xtrac tion of wate r into the ultrafiltrate
D) Has a higher hydrostatic pressure than afferent arteriolar blood
E) Has the same hydrostatic pressure as afferent ateriolar blood because the efferent arter iole co nstric ts

Question 16

Which is NOT a fundamental or elementary process of the nephron?

A) Ultrafiltration
B) Proteolytic degradation
C) Reabsorption
D) Secretion
E) Movem ent of material from lumen to peritubular capillaries