Osmometry + Urines

Question 1

What effect will one mole of a non-electrolyte have on the freezing point of one kilogram of water?

Answer 1

It will depress the freezing point by 1.86°C

Question 2

Definition of osmolality

Answer 2

The number of ionized particles dissolved in 1 kg of solution

Question 3

Formula for serum calculated osmolality

Answer 3

1.86 [sodium] + glucose + urea + 9

Question 4

The most practical measure to screen for volatile substances

Answer 4

Freezing point depression osmometry

Question 5

What could be a possible effect on osmometry testing if alcohol was used to clean the osmometer?

Answer 5

Falsely increased osmolality results

Question 6

Cause of prefreeze in freezing point depression osmometry

Answer 6

Presence of particulate matter in the sample

Question 7

The normal renal threshold for glucose

Answer 7

10 mmol/L

Question 8

A urine specimen excreted by a rugby patient after being admitted to hospital for torn ligaments incurred during a game showed a positive dipstick test for blood, but microscopic examination of the sediment revealed no increase in the number of erythrocytes. The apparent discrepancy may be due to the presence of:

Answer 8

Myoglobin

Question 9

A urine containing 0-5 hyaline casts/LPF would likely give a positive reaction for which urinalysis test?

Answer 9

Protein

Question 10

The protein constituent composing the matrix of a hyaline cast

Answer 10

Tamm-Horsfall protein

Question 11

A precipitating agent used to detect protein in urine

Answer 11

Sulfosalicylic acid

Question 12

The appearance of glucose in the urine of a patient with a normal blood glucose level is indicative of:

Answer 12

A lowered renal threshold

Question 13

What is ethanol metabolized to?

Answer 13

Acetaldehyde

Question 14

For what colorimetric determination is the Trinder reaction widely used?

Answer 14

Salicylate

Question 15

Microalbuminuria

Answer 15

Presence of low concentrations of albumin in the urine

Question 16

Usual cause of urine with pH greater than 8

Answer 16

Proliferation of urease producing bacteria

Question 17

Appearance of triple phosphate crystals

Answer 17

Coffin lids

Question 18

Which urine crystal resembles coffin lids?

Answer 18

Triple phosphate

Question 19

Oval fat bodies seen microscopically in a urine specimen consist of:

Answer 19

RTEs filled with fat

Question 20

Increased leukocytes in a urine specimen without casts indicates:

Answer 20

Lower urinary tract infection

Question 21

A jaundiced patient with a positive urine bilirubin and a negative urine urobilinogen probably has what type of jaundice?

Answer 21

Posthepatic jaundice