AMERICAN ALLIED HEALTH ACTUAL EXAM
QUESTIONS WITH ANSWERS GRADED A+
2025/2026
1. Which blood specimen additive can inhibit the metabolism of glucose by the
cells?
a. EDTA
b. Heparin
c. NaF
d. Oxalate
1. Answer: c
WHY: A substance that prevents glycolysis, the breakdown, or metabolism of
glucose (blood sugar) by blood cells, is called a glycolytic inhibitor or an
antiglycolytic agent. The most common antiglycolytic agent is sodium fluoride
(NaF). It preserves glucose for up to three days and also inhibits the growth of
bacteria.
2. All of the following items are part of the equipment needed to perform a
routine venipuncture EXCEPT which?
a. Disinfectant
b. Evacuated tubes
c. Safety needle
d. Tourniquet
2. Answer: a
WHY: Antiseptics, not disinfectants, are routinely used when performing
venipuncture. Disinfectants are chemical substances or solutions that are used to
remove or kill microorganisms on surfaces and instruments. They are typically
corrosive and not safe for use on human skin.
,3. Which of the following evacuated tubes can be used to collect a serum
specimen?
a. EDTA
b. PPT
c. PST
d. SST
3. Answer: d
WHY: SST stands for serum separator tube. The tube does not contain an
anticoagulant, so blood collected in it will yield serum. The EDTA tube and plasma
preparation tube (PPT) both contain the anticoagulant EDTA. The plasma
separator tube (PST) contains the anticoagulant heparin. Anticoagulants prevent
the blood from clotting and yield plasma when centrifuged.
4. Which of the following are all anticoagulants that prevent coagulation by
binding or precipitating calcium?
a. EDTA, lithium heparin, citrate
b. NaF, sodium heparin, EDTA
c. Oxalate, SPS, sodium heparin
d. Sodium citrate, EDTA, oxalate
4. Answer: d
WHY: Sodium citrate, oxalate, and EDTA are all anticoagulants that prevent blood
from clotting by chelating (binding) or precipitating calcium so it is not available to
the coagulation process. Sodium polyanethol sulfonate (SPS) also binds calcium,
though lithium and sodium heparin prevent clotting by inhibiting the formation of
thrombin needed to convert fibrinogen to fibrin in the coagulation process.
Sodium fluoride (NaF) is an antiglycolytic agent, not an anticoagulant.
5. During a successful venipuncture, evacuated tubes fill automatically when the
tube stopper is pierced because of
a. equal pressure in the vein and tube.
b. premeasured vacuum in each tube.
c. pressure from the arterial system.
d. tourniquet pressure on the vein.
5. Answer: b
,WHY: Evacuated tubes fill with blood automatically because there is a vacuum
(negative pressure) in them. The vacuum is premeasured by the manufacturer so
that the tube will draw the precise volume of blood indicated.
6. Lavender stopper tubes are most commonly used to collect
a. chemistry tests.
b. coagulation tests.
c. hematology tests.
d. immunology tests.
6. Answer: c
WHY: EDTA prevents coagulation and is primarily used to provide whole blood
specimens for hematology tests because it preserves cell morphology and inhibits
platelet aggregation or clumping.
7. Which of the following is one reason the evacuated tube system is the
preferred blood collection system?
a. Exposure of the blood to contaminants is avoided.
b. Needles used with the ETS have a smaller lumen.
c. The collector's exposure to blood is eliminated.
d. Using a syringe can collapse a vein more easily.
7. Answer: a
WHY: The most common, efficient, and CLSI-preferred system for collecting blood
samples is the ETS. It is a closed system in which the patient's blood flows directly
into a collection tube, without being exposed to air or outside contaminants.
Blood collected in a syringe is exposed to air and the possibility of outside
contamination. In addition, the needle must be removed from a syringe to attach
a transfer device used to fill the tubes. This can expose the user to the patient's
blood. The ETS minimizes the collector's exposure to blood but does not eliminate
it as there is often a small amount of blood on the stopper where the needle
entered the tube. The ETS system can collapse a fragile vein more easily than a
syringe. The vacuum pull of a syringe can be adjusted to minimize the chance of
vein collapse. Syringe needles are available in the same gauges as ETS needles, so
an equivalent gauge ETS needle would have the same size lumen as a syringe
needle.
, 8. Lithium heparin is a suitable anticoagulant for which of the following tests?
a. CBC
b. Lytes
c. Lithium
d. Protime
8. Answer: b
WHY: Lithium heparin causes the least interference in chemistry testing and is the
most widely used anticoagulant for plasma and whole-blood chemistry tests.
Heparinized plasma is often used for STAT chemistry tests and other rapid-
response situations when a fast turnaround time (TAT) for chemistry tests is
needed.
9. Which additive is in some royal blue-top tubes?
a. Citrate
b. EDTA
c. Fluoride
d. Oxalate
9. Answer: b
WHY: Royal blue-top tubes contain EDTA, heparin, or no additive to meet various
test requirements. Tube labels are typically color coded to indicate the type of
additive, if any, in the tube.
10. Measurement of copper, a trace element, normally requires blood collection
in a tube with a
a. green top.
b. lavender top.
c. light blue top.
d. royal blue top.
10. Answer: d
WHY: Royal blue-top tubes are made of materials that are as free of trace-
element contamination as possible and are used for trace-element tests, such as
copper.
QUESTIONS WITH ANSWERS GRADED A+
2025/2026
1. Which blood specimen additive can inhibit the metabolism of glucose by the
cells?
a. EDTA
b. Heparin
c. NaF
d. Oxalate
1. Answer: c
WHY: A substance that prevents glycolysis, the breakdown, or metabolism of
glucose (blood sugar) by blood cells, is called a glycolytic inhibitor or an
antiglycolytic agent. The most common antiglycolytic agent is sodium fluoride
(NaF). It preserves glucose for up to three days and also inhibits the growth of
bacteria.
2. All of the following items are part of the equipment needed to perform a
routine venipuncture EXCEPT which?
a. Disinfectant
b. Evacuated tubes
c. Safety needle
d. Tourniquet
2. Answer: a
WHY: Antiseptics, not disinfectants, are routinely used when performing
venipuncture. Disinfectants are chemical substances or solutions that are used to
remove or kill microorganisms on surfaces and instruments. They are typically
corrosive and not safe for use on human skin.
,3. Which of the following evacuated tubes can be used to collect a serum
specimen?
a. EDTA
b. PPT
c. PST
d. SST
3. Answer: d
WHY: SST stands for serum separator tube. The tube does not contain an
anticoagulant, so blood collected in it will yield serum. The EDTA tube and plasma
preparation tube (PPT) both contain the anticoagulant EDTA. The plasma
separator tube (PST) contains the anticoagulant heparin. Anticoagulants prevent
the blood from clotting and yield plasma when centrifuged.
4. Which of the following are all anticoagulants that prevent coagulation by
binding or precipitating calcium?
a. EDTA, lithium heparin, citrate
b. NaF, sodium heparin, EDTA
c. Oxalate, SPS, sodium heparin
d. Sodium citrate, EDTA, oxalate
4. Answer: d
WHY: Sodium citrate, oxalate, and EDTA are all anticoagulants that prevent blood
from clotting by chelating (binding) or precipitating calcium so it is not available to
the coagulation process. Sodium polyanethol sulfonate (SPS) also binds calcium,
though lithium and sodium heparin prevent clotting by inhibiting the formation of
thrombin needed to convert fibrinogen to fibrin in the coagulation process.
Sodium fluoride (NaF) is an antiglycolytic agent, not an anticoagulant.
5. During a successful venipuncture, evacuated tubes fill automatically when the
tube stopper is pierced because of
a. equal pressure in the vein and tube.
b. premeasured vacuum in each tube.
c. pressure from the arterial system.
d. tourniquet pressure on the vein.
5. Answer: b
,WHY: Evacuated tubes fill with blood automatically because there is a vacuum
(negative pressure) in them. The vacuum is premeasured by the manufacturer so
that the tube will draw the precise volume of blood indicated.
6. Lavender stopper tubes are most commonly used to collect
a. chemistry tests.
b. coagulation tests.
c. hematology tests.
d. immunology tests.
6. Answer: c
WHY: EDTA prevents coagulation and is primarily used to provide whole blood
specimens for hematology tests because it preserves cell morphology and inhibits
platelet aggregation or clumping.
7. Which of the following is one reason the evacuated tube system is the
preferred blood collection system?
a. Exposure of the blood to contaminants is avoided.
b. Needles used with the ETS have a smaller lumen.
c. The collector's exposure to blood is eliminated.
d. Using a syringe can collapse a vein more easily.
7. Answer: a
WHY: The most common, efficient, and CLSI-preferred system for collecting blood
samples is the ETS. It is a closed system in which the patient's blood flows directly
into a collection tube, without being exposed to air or outside contaminants.
Blood collected in a syringe is exposed to air and the possibility of outside
contamination. In addition, the needle must be removed from a syringe to attach
a transfer device used to fill the tubes. This can expose the user to the patient's
blood. The ETS minimizes the collector's exposure to blood but does not eliminate
it as there is often a small amount of blood on the stopper where the needle
entered the tube. The ETS system can collapse a fragile vein more easily than a
syringe. The vacuum pull of a syringe can be adjusted to minimize the chance of
vein collapse. Syringe needles are available in the same gauges as ETS needles, so
an equivalent gauge ETS needle would have the same size lumen as a syringe
needle.
, 8. Lithium heparin is a suitable anticoagulant for which of the following tests?
a. CBC
b. Lytes
c. Lithium
d. Protime
8. Answer: b
WHY: Lithium heparin causes the least interference in chemistry testing and is the
most widely used anticoagulant for plasma and whole-blood chemistry tests.
Heparinized plasma is often used for STAT chemistry tests and other rapid-
response situations when a fast turnaround time (TAT) for chemistry tests is
needed.
9. Which additive is in some royal blue-top tubes?
a. Citrate
b. EDTA
c. Fluoride
d. Oxalate
9. Answer: b
WHY: Royal blue-top tubes contain EDTA, heparin, or no additive to meet various
test requirements. Tube labels are typically color coded to indicate the type of
additive, if any, in the tube.
10. Measurement of copper, a trace element, normally requires blood collection
in a tube with a
a. green top.
b. lavender top.
c. light blue top.
d. royal blue top.
10. Answer: d
WHY: Royal blue-top tubes are made of materials that are as free of trace-
element contamination as possible and are used for trace-element tests, such as
copper.
