ASCP-MLT Online Practice Questions and Answers

Free T4 is affected the least by changes in plasma proteins during pregnancy. Which of the following thyroid function assays is affected least by pregnancy:

A. Total T3

B. Total T4

C. Free T4

Bacitracin susceptibility is a presumptive test for the identification of Lancefield group A Streptococcus.

Which of the following is a presumptive test for the identification of Lancefield group A Streptococcus:

A. Bacitracin susceptibility

B. Positive coagulase

C. Hippurate hydrolysis

D. Gram stain

A. glass tubes contain heparin

B. plastic tubes contain a clot activator

C. plastic tubes are recommended for blood bank tests

D. glass tubes cannot be used for serology tests

Platelet neutralization tests are one of the confirmatory tests that can be used to determine if a patient has a circulating lupus antibody, or lupus anticoagulant. The principle in this test involved the use of a freeze-thawed platelet suspension that, when mixed with the patient plasma, will neutralize the anti-phospholipid antibodies (lupus anticoagulant) present and allow for a corrected aPTT result upon re-testing. A patient has a history of repeated spontaneous abortion. Coagulation studies reveal an elevated APTT, normal PT, normal platelet function, and normal clotting time. Schistocytes were seen on the peripheral blood smear.

Which test should be performed to determine if the patient has lupus anticoagulant?

A. Factor VIII assay

B. mixing studies with factor-deficient plasma

C. antinuclear antibody test

D. platelet neutralization test

Electrophoresis uses an electric field to separate molecules based on differences in net electrical charge. The rate of electrophoretic migration is also dependent on the ionic radius of the molecule, the viscosity of the solution through which it is migrating, the electrical field strength, temperature, and the type of supporting medium used.

Electrophoretic separation fundamentally relies on:

A. Size differences of molecules

B. Net charge differences of molecules

C. Concentration differences of molecules

D. Shape variations of molecules

1 SD = 68.3%, 2 SD = 95.5%, 3 SD = 99.7

As defined by a Gaussian distribution curve, what percentage of values would be expected to fall within two standard deviations of the mean:

A. 75%

B. 85%

C. 95%

D. 100%

Gamma globulin (anti-D) is given to Rh-negative mothers to prevent any D antibody production, which could cause harmful effects in future pregnancies with an Rh-positive fetus. The administered anti-D will bind fetal Rh-positive cells that may come from the fetus in vivo; therefore the mother will not produce anti-D herself, preventing sensitization.

A solution of gamma globulins containing anti-Rh (D) is given to an Rh (D) negative mother to:

A. Prevent fetal cells from initially sensitizing the mother

B. Neutralize any of the child's antibody that may have passed the placental barrier

C. Neutralize any natural maternal antibodies present

D. Prevent greater antibody response in a previously sensitized mother

Alpha-fetoprotein is a substance typically used in the triple test during pregnancy and for screening chronic liver disease patients for hepatocellular carcinoma. Increased concentrations of alpha-fetoprotein (AFP) in adults are MOST characteristically associated with:

A. hepatocellular carcinoma

B. alcoholic cirrhosis

C. chronic active hepatitis

D. multiple myeloma

The lactophenol blue mount reveals tiny, ovoid microconidia, arranged in a daisy-head pattern at the tip of a straight conidiophore. This appearance is characteristic of the mold form of Sporothrix schenckii. By moving the focus up and down

in a microscopic preparation, delicate hair-like attachments may be observed for each conidium.

The mold form of Coccidioides immitis produces delicate hyphae that break up into arthroconidia separated by empty cells, giving an alternatively staining appearance.

The mold form of Blastomyces dermatitidis is characterized by the production of single, smooth microconidia, each borne on a single, thin conidiophore ("lollipops").

The mold form of Histoplasma capsulatum is recognized by the production of large, echinulate macroconidia, appearing as a prickly surface.

The ovoid microconidia arranged in a daisy-head pattern at the tip of a a straight conidiophore, observed in the photomicrograph on the right, is characteristic of which of the following dimorphic molds?

A. Sporothrix schenckii

B. Coccidioides immitis

C. Blastomyces dermatitidis

D. Histoplasma capsulatum

All the following characteristics are accurate for the influence of Health Insurance Portability and Accountability Act (HIPAA) except

A. Establishes a minimum standard for security of electronic health information and the electronic interchange of information

B. Replaced federal, state, or other laws that grant individuals even greater privacy protections than HIPAA

C. Directly effects the laboratory information system (LIS)

D. Covers entities that are free to retain or adopt more protective policies or practices

First, determine the number of WBC's from the hemocytometer as follows:

WBC count = (dilution ratio x # of cells counted x 10) / (# mm2 area counted) Then: WBC count = (20 x 100 x 10) / (8) = 2500 WBC/mm3 (or 2500 WBC/uL or 2.5 x 103 WBC/uL)

Next, to find the WBC count per liter, multiply the WBC count/uL by the number of uL/L (there are 106 uL/L)

So: (2.5 x 103 WBC/uL) x (106 uL/L) = 2.5 x 109 WBC/L

Hematology

A 1:20 dilution is made for a manual WBC count. The four corner squares on both sides of a hemocytometer are counted. A TOTAL of 100 cells are counted in that area. What is the white blood cell count in terms of a liter (? x 10^9/L)?

A. 2.5

B. 25

C. 250

D. 2500

E. 25000

The term affinity refers to the strength of attraction between a single antigenic determinant and a corresponding antigen binding site. The term avidity refers to the total strength of the attraction between an antibody and a multivalent antigen. The reaction between an IgM molecule (which has 10 antigen binding sites), and a multivalent antigen is therefore much stronger than that of an IgG antibody (which has only 2 antigen binding sites).

Avidity is best described by which of the following statements:

A. The strength with which red cells agglutinate

B. The strength with which multivalent antigens and antibodies bind

C. The strength with which univalent antigens and antibodies bind

D. The speed with which an antigen-antibody reaction occurs

Which of the following Rh antigens is found the highest frequency in the Caucasian population:

A. C

B. E

C. c

D. e

Osteoblasts are generally seen in clusters while plasma cells are often more diffusely distributed. Osteoblasts have delicate cytoplasm, whereas plasma cells have dense basophilic cytoplasm with a perinuclear halo.

Hematology

The large cell shown in the illustration to the right is occasionally seen in the bone marrow and can be mistaken for a plasma cell - what is this cell called:

A. Myeloblast

B. Osteoblast

C. Stem cell

D. Megakaryoblast

An antithetical relationship exists between the antigens M and N. Antithetical relationships occur in situations where for a given locus, only one of two genes may be inherited, the alleles are termed antithetical alleles. In immunohematology, an antithetical relationship exists between M antigen and which of these antigens?

A. K

B. S

C. Vw

D. N