CMLA Specimen Collection & Processing 3

Question 1

What is the primary purpose of centrifugation in blood specimen processing?

Accepted Answer

To separate cellular components from plasma or serum for testing

Answer

To sterilize the specimen before analysis

Answer

To lyse red blood cells for easier analysis

Answer

To concentrate analytes for low-volume samples

Question 2

Which specimen type requires protection from light during collection and transport to the laboratory?

Accepted Answer

Bilirubin and porphyrins

Answer

Serum for basic metabolic panel

Answer

CBC in EDTA tube

Answer

Urine pregnancy test

Question 3

What does the abbreviation SST stand for in the context of laboratory specimen collection?

Accepted Answer

Serum Separator Tube

Answer

Sterile Sample Tube

Answer

Standard Specimen Transport

Answer

Sequential Sampling Technique

Question 4

When performing a capillary (fingerstick) blood collection, which part of the finger is the preferred puncture site?

Accepted Answer

The center pad of the middle or ring finger, slightly to one side

Answer

The very tip of the index finger

Answer

The base of the thumb near the palm

Answer

The lateral edge of the pinky finger

Question 5

What is the maximum acceptable time limit for processing most blood specimens (centrifuging serum or plasma) after collection?

Accepted Answer

2 hours

Answer

30 minutes

Answer

8 hours

Answer

24 hours

Question 6

Which anticoagulant mechanism in EDTA (lavender) tubes prevents blood from clotting?

Accepted Answer

Chelating (binding) calcium ions needed for the coagulation cascade

Answer

Inhibiting thrombin directly

Answer

Destroying fibrinogen in the plasma

Answer

Activating antithrombin III

Question 7

If a blood specimen appears visibly lipemic (milky white), what should the laboratory assistant do?

Accepted Answer

Document the lipemia, notify the laboratory supervisor, and note it may interfere with certain assays

Answer

Proceed with testing as normal; lipemia has no effect on results

Answer

Dilute the sample with saline 1:1 before analysis

Answer

Recollect the specimen immediately using a different tube type