cc lab finals

Question 1

containing compounds that are not proteins or polypeptides

Answer 1

nitrogen

Question 2

Total NPN can be tested by making a

Answer 2

protein-free filtrate

Question 3

Highest concentration of NPN in blood

Answer 3

Urea, 45%

Question 4

Urea is synthesized in the

Answer 4

liver, from CO2 and ammonia, as the final product of amino acid catabolism.

Question 5

is a nonspecific indicator of renal function

Answer 5

urea

Question 6

States associated with elevated levels of urea in blood are referred to as

Answer 6

uremia & azotemia

Question 7

Causes of urea plasma elevations

Answer 7

◼ Prerenal
◼ Renal
◼ and postrenal

Question 8

is performed to differentiate between pre-renal and post-renal azotemia.

Answer 8

Parallel determination of urea and creatinine

Question 9

Specimen for BUN

Answer 9

Serum and heparinized plasma

Question 10

Enzymatic Method

Answer 10

◉ Nessler’s Method
◉ Berthelot Reaction
◉ Urease/GLDH Method

Question 11

Urea is converted to ammonia by the enzyme urease.

Answer 11

NESSLER’S METHOD

Question 12

Ammonia reacts with Nessler’s reagent giving rise to a

Answer 12

brown colored compound which is read at 450 nm.

Question 13

Nessler’s reagent is composed of

Answer 13

potassium mercuric iodide.

Question 14

Disadvantages of nessler method

Answer 14

􏰀 Colour instability.
􏰀 Turbidity.
􏰀 Nonlinear calibration