The first use of citrate as an anticoagulant to prevent blood from clotting during transfusion occurred in
a. 1901
b. 1914
c. 1957
d. 1943
b. 1914
Which of the folfowing best describes the function of ATP in maintalning red blood cell (RBC) membrane Integrity and homeostasis?
A. It facilitates the passive movement of chloride and bicarbonate across the membrane
B. It powers cation pumps that regulate intracellular sodium. potassium, and talcium levels
C. It increases membrane permeability to water and large proteins
D. It transports oxygen and carbon dioxide directly through the cytoskeleton
B. It powers cation pumps that regulate intracellular sodium. potassium, and talcium levels
The average RBCIlfespan Is:
A. 30 days
B. 90 days
C 110 days
D. NOTA
D. NOTA
What structural feature allows the red blood cell (RBC) to maintain its biconcave shape and flexibility?
A. Lipid bilayer only
B. Integral membrane proteins only
C. Peripheral proteins forming the cytoskeleton
D. Hemoglobin spncentration
C. Peripheral proteins forming the cytoskeleton
What is the name of the protein around which DNA winds to form nucleosomes and help in chromatin packaging within the nucleus?
Histones
Why does an acute hemolytic transfusion reaction caused by ABO incompatibility usually result in intravascular hemolysis?
A. Because IgM antibodies acivate complement, leading to red cell lysis inside blood vessels
B. Because IgG antibodies promote red cell clearance in the spleen
C. Because red cells are gradually destroyed by the liver
D. Because warm autoantibodies coat red cells for phagocytosis
A. Because IgM antibodies acivate complement, leading to red cell lysis inside blood vessels
Which statement best describes the development and characteristics of ABO antibodies?
A. They are absent at birth and begini to appear only after puberty.
B. At birth, detectable IgM ABO antibodies are already present in high titer.
C. Maternal IgG provides ABO antibodies at birth, while the infant’s own antibodies reach detectable levels by 3-6 months and peak at
5-10 years, predominantly as IgM in adults.
D. ABO antibodias are mainly IgA and do not change with age.
C. Maternal IgG provides ABO antibodies at birth, while the infant’s own antibodies reach detectable levels by 3-6 months and peak at
5-10 years, predominantly as IgM in adults.
In the ABO system, which sugar does the A transferase add to the H antigen?
A. N-acetylgalactosamine
B. D-galactose
C. N-acety!glucosamine
D. Fucose
A. N-acetylgalactosamine
Which ABO phenotype has the highest amount of H antigen expression on red cells?
A. Group A
B. Group B
С. Group AB
D. Group O
D. Group O
In adults, ABO antibodies are predominantly which immunoglobulin class?
A, IBA
B. IgG
C. IgM
D. IgE
C. IgM
Which antigen in the Rh system is the most clinically significant due to its strong immunogenicity?
A. C
B. с
C. D
D. E
C. D
Why are anti-D antibodies usually formed only after exposure to Rh-positive red cells (e.g., through pregnancy or transfusion)?
A. Because anti-D is naturally occurring like ABO antibodies
B. Because D antigen is a weak immunogen and easily tolerized
C. Because anti-D is an immune antibody produced only after sensitization
D. Because Rh antibodies are IgA and short-lived
C. Because anti-D is an immune antibody produced only after sensitization
Which immunoglobulin class is most typical for anti-D antibodies?
A. IgM
B. IBA
C. IgE
D. IgG
D. IgG
Which term describes a person with a qualitative weak expression of the D antigen, leading to variable serologic detection?
A. Rhnull
B. Partial D
C. Weak D
D. Bombay phenotype
C. Weak D
A patient is typed as Rh-negative by routine testing, but molecular testing shows the presence of a weak D allele. Which is the safest practice in transfusion?
A. Treat as Rh-positive donor, Rh-negative recipient
B. Treat as Rh-negative donor and Rh-negative recipient
C. Treat as Rh-positive in all cases
D. Ignore weak D typing results
B. Treat as Rh-negative donor and Rh-negative recipient
Which nomenclature system expresses Rh antigens as without assuming genetic mechanisms?
A. Fisher-Race
B. Wiener
С. Rosenfield
D. ISBT
С. Rosenfield
A patient’s red cell phenotype is DCe/DCe in Fisher-Race. How is this written in Wiener notation?
A. R1R1
B. RORO
C. R2R2
D. rr
A. R1R1
Which statement best describes the Lewis antigens?
A. They are intemsic to the red blood cell membrane.
B. They are manufactured by tissue cells and secreted into plasma, then adsorbed onto RBCs.
C. They are present only in fetal life and disappear after birth.
D. They are expressed only when the person is a secretor.
B. They are manufactured by tissue cells and secreted into plasma, then adsorbed onto RBCs.
Which of the following Lewis phenotypes is most common in adults?
A. Le(a+b-)
B. Le(a-b+)
C. Le(a+b+)
D. Le(a-b-)
B. Le(a-b+)
What genetic interaction determines whether Le(b) antigen will be expressed?
A. Only the Lewis (Le) gene is required
B. Lewis gene + Secretor (Se) gene
C. Lewis gene + H gene
D. Secretor gene alone
B. Lewis gene + Secretor (Se) gene
Which is true about Lewis antibodies?
A. They are usually IgG and clinicallysignificant
B. They can cause severe hemolytic disease of the fetus and newborn (HDFN)
C. They are usually naturally occurring IgM and not clinically significant
D. They are routinely sought in prenatal antibody screening.
C. They are usually naturally occurring IgM and not clinically significant
Which antibody is associated with paroxysmal cold hemoglobinuria (PCH)?
A. Anti-P
B. Anti-P1
C. Anti-Pk
D. Anti-NOR
A. Anti-P
Which antigen in the P/P1PK system is recognized as the globoside receptor used by Parvovirus B19 for host cell entry?
A. P antigen
B. P1 antigen
C. Pk antigen
D. PP1Pk antigen
A. P antigen
A woman with recurrent spontaneous abortions is - found to have an antibody in the P/P1PK system. Which antibody is most likely implicated?
A. Anti-P1
B. Anti-PP1Pk
C. Anti-Pk
D. Anti-P
B. Anti-PP1Pk
