NPN: Urea

Question 1

total NPN of urea

urea has the highest concentration among other NPNs

Answer 1

45-50%

Question 2

T/F. urea is the major excretory product of the metabolism of proteins

Answer 2

TRUE

Question 3

concentration is expressed in terms of nitrogen content

Answer 3

BUN x 2.14 = urea

Question 4

how to get urea -> BUN

Answer 4

urea/2.14=BUN

Question 5

reference method

Answer 5

Isotope Dilution Method (IDMS)

Question 6

Fearon Method
Reagent:
Product:

Answer 6

rgt.: Diacetyl monoxime
prod.: diazine (yellow)

Question 7

rgt.: K2(HgI4)
prod.: ammonium dimercuric iodide

Answer 7

Nesslerization

Question 8

Nesslerization end product

Answer 8

yellow

Question 9

rgt.: sodium nitroprusside
prod.: indophenol

Answer 9

Berthelot

Question 10

Berthelot end product

Answer 10

blue

Question 11

citrate and fluoride inhibits

Answer 11

urease

Question 12

GLDH-Couple Enzymatic absorbance

Answer 12

↓A@340nm

Question 13

measurement of the increase in conductivity due to NH4+ and CO3^2- ions

↑ urea ↑ ammonium

Answer 13

conductimetric

Question 14

Reference range

Answer 14

6-20mg/dL BUN

Question 15

Conversion factor

Answer 15

0.357

Question 16

pre-renal
renal
post-renal

Answer 16

azotemia

Question 17

↑ BUN, normal Crea

Answer 17

pre-renal

Question 18

dehydration
↓ blood volume
high-protein diet
↑ protein catabolism

Answer 18

pre-renal

Question 19

↑BUN, ↑crea

Answer 19

renal
post-renal

Question 20

↓ excretion
(glomerulonephritis, renal failure)

Answer 20

renal

Question 21

urinary tract obstruction
(nephrolithiasis, tumors, severe infection)

Answer 21

post-renal

Question 22

very high plasma urea accompanied by renal failure

↑ BUN, ↑ crea, ↓GFR (Glomerular Filtration Rate)

Answer 22

uremia/uremic syndrome