What type of serological testing does the blood
bank technologist perform when determining the
blood group of a patient? - ANSWER phenotyping
If anti-K reacts 3+ with a donor cell with a
genotype KK and 2+ with a Kk cell, the antibody
is demonstrating: - ANSWER Dosage
Carla expresses the blood group antigens Fya, Fyb, and Xga. James shows expressions of
none of these antigens. What factor(s) may account for the absence of these antigens in
James? - ANSWER Gender and Race. The frequency of Duffy antigens Fya and Fyb varies
with race. The Fy(a−b−) phenotype occurs in almost
70% of African Americans and is very rare in whites.
The Xga antigen is X-linked and, therefore, expressed more frequently in women (who may
inherit the antigen from either parent) than in men.
Which of the following statements is true?
A. An individual with the BO genotype is
homozygous for B antigen
B. An individual with the BB genotype is
homozygous for B antigen
C. An individual with the OO genotype is
heterozygous for O antigen
D. An individual with the AB phenotype is
1
,homozygous for A and B antigens - ANSWER B. An individual with the BB genotype is
homozygous for B antigen
Which genotype is heterozygous for C?
A. DCe/dce
B. DCE/DCE
C. Dce/dce
D. DCE/dCe - ANSWER A. DCe/dce
Which genotype(s) will give rise to the Bombay phenotype? - ANSWER The Bombay phe-
notype will be expressed only when no H substance is present. The Oh type is expressed by
the genotype hh. Bombays produce naturally occurring anti-H, and their serum agglutinates
group
O red cells in addition to red cells from groups A, B, and AB persons.
Meiosis in cell division is limited to the ova and sperm producing four gametes containing
what complement of DNA? - ANSWER 1N. Meiosis involves two nuclear divisions in suc-
cession resulting in four gametocytes each containing half the number of chromosomes
found in somatic cells or 1N.
A cell that is not actively dividing is said to be in: - ANSWER Interphase, The cell is en-
gaged in metabolic activity. Chromosomes are not clearly discerned; however, nucleoli may
be
visible
Which of the following describes the expression of most blood group antigens? - AN-
SWER Codominant
What blood type is not possible for an offspring of an AO and BO mating? - ANSWER All
are possible
2
,The alleged father of a child in a disputed case of paternity is blood group AB. The mother is
group O and the child is group O. What type of exclusion is this? - ANSWER -Indirect/sec-
ondary/second order
An indirect/secondary/second order exclusion occurs when a genetic marker is absent in the
child but should have been transmitted by the alleged father. In this case, either A or B
should be present in the child.
If the frequency of gene Y is 0.4 and the frequency of gene Z is 0.5, one would expect that
they should occur together 0.2 (20%) of the time. In actuality,
they are found together 32% of the time. This is an example of: - ANSWER Linkage dise-
quilibrium.
Linkage disequilibrium is a phenomenon in which alleles situated in close proximity on a
chromosome associate with one another more than would be expected from individual al-
lelic frequencies.
In this type of inheritance, the father carries the trait on his X chromosome. He has no sons
with the trait because he passed his Y chromosome to his sons; however, all his daughters
will express the trait. - ANSWER Autosomal Dominant
In the Hardy-Weinberg formula, p2 represents: - ANSWER In the Hardy-Weinberg formula
p2 + 2pq + q2, p2 and q2 represent homozygous expressions and 2pq represents heterozy-
gous expression. This formula is
used in population genetics to determine the frequency of different alleles.
What is the Hardy-Weinberg formula? - ANSWER p2 + 2pq + q2 = 1
Why do IgM antibodies, such as those formed against the ABO antigens, have the ability to
directly agglutinate red blood cells (RBCs) and cause visible agglutination? - ANSWER IgM
antibodies are larger molecules and have the ability to bind more antigen
3
, Which of the following enhancement mediums decreases the zeta potential, allowing anti-
body and antigen to come closer together? - ANSWER LISS.
LISS contains a reduced concentration of NaCl (0.2%) and results in a reduction in charged
ions within the ionic cloud, decreasing the zeta potential and facilitating antigen and anti-
body interaction.
This type of antibody response is analogous to an anamnestic antibody reaction. - AN-
SWER Secondary.
An anamnestic response is a secondary immune response in which memory lymphocytes re-
spond rapidly to foreign antigen in producing specific antibody. The antibodies are IgG and
are produced
at lower doses of antigen than in the primary response.
Which antibodies to a component of complement are contained in the rabbit polyspecific
antihuman globulin reagent for detection of in vivo sensitization? - ANSWER In the DAT
(direct antiglobulin test), rabbit
polyspecific antisera contains both an anti-human IgG component and an antibody against
the C3d component of complement.
Which of the following distinguishes A1 from A2 blood groups?
A. A2 antigen will not react with anti-A, A1 will
react strongly (4+)
B. An A2 person may form anti-A1; an A1 person
will not form anti-A1
C. An A1 person may form anti-A2, an A2 person
will not form anti-A1
D. A2 antigen will not react with anti-A from a nonimmunized donor; A1 will react with any
anti-A - ANSWER B. An A2 person may form anti-A1; an A1 person will not form anti-A1
A patient's serum is incompatible with O cells. The patient RBCs give a negative reaction to
anti-H lectin. What is the most likely cause of these results? - ANSWER Bombay is the
4
bank technologist perform when determining the
blood group of a patient? - ANSWER phenotyping
If anti-K reacts 3+ with a donor cell with a
genotype KK and 2+ with a Kk cell, the antibody
is demonstrating: - ANSWER Dosage
Carla expresses the blood group antigens Fya, Fyb, and Xga. James shows expressions of
none of these antigens. What factor(s) may account for the absence of these antigens in
James? - ANSWER Gender and Race. The frequency of Duffy antigens Fya and Fyb varies
with race. The Fy(a−b−) phenotype occurs in almost
70% of African Americans and is very rare in whites.
The Xga antigen is X-linked and, therefore, expressed more frequently in women (who may
inherit the antigen from either parent) than in men.
Which of the following statements is true?
A. An individual with the BO genotype is
homozygous for B antigen
B. An individual with the BB genotype is
homozygous for B antigen
C. An individual with the OO genotype is
heterozygous for O antigen
D. An individual with the AB phenotype is
1
,homozygous for A and B antigens - ANSWER B. An individual with the BB genotype is
homozygous for B antigen
Which genotype is heterozygous for C?
A. DCe/dce
B. DCE/DCE
C. Dce/dce
D. DCE/dCe - ANSWER A. DCe/dce
Which genotype(s) will give rise to the Bombay phenotype? - ANSWER The Bombay phe-
notype will be expressed only when no H substance is present. The Oh type is expressed by
the genotype hh. Bombays produce naturally occurring anti-H, and their serum agglutinates
group
O red cells in addition to red cells from groups A, B, and AB persons.
Meiosis in cell division is limited to the ova and sperm producing four gametes containing
what complement of DNA? - ANSWER 1N. Meiosis involves two nuclear divisions in suc-
cession resulting in four gametocytes each containing half the number of chromosomes
found in somatic cells or 1N.
A cell that is not actively dividing is said to be in: - ANSWER Interphase, The cell is en-
gaged in metabolic activity. Chromosomes are not clearly discerned; however, nucleoli may
be
visible
Which of the following describes the expression of most blood group antigens? - AN-
SWER Codominant
What blood type is not possible for an offspring of an AO and BO mating? - ANSWER All
are possible
2
,The alleged father of a child in a disputed case of paternity is blood group AB. The mother is
group O and the child is group O. What type of exclusion is this? - ANSWER -Indirect/sec-
ondary/second order
An indirect/secondary/second order exclusion occurs when a genetic marker is absent in the
child but should have been transmitted by the alleged father. In this case, either A or B
should be present in the child.
If the frequency of gene Y is 0.4 and the frequency of gene Z is 0.5, one would expect that
they should occur together 0.2 (20%) of the time. In actuality,
they are found together 32% of the time. This is an example of: - ANSWER Linkage dise-
quilibrium.
Linkage disequilibrium is a phenomenon in which alleles situated in close proximity on a
chromosome associate with one another more than would be expected from individual al-
lelic frequencies.
In this type of inheritance, the father carries the trait on his X chromosome. He has no sons
with the trait because he passed his Y chromosome to his sons; however, all his daughters
will express the trait. - ANSWER Autosomal Dominant
In the Hardy-Weinberg formula, p2 represents: - ANSWER In the Hardy-Weinberg formula
p2 + 2pq + q2, p2 and q2 represent homozygous expressions and 2pq represents heterozy-
gous expression. This formula is
used in population genetics to determine the frequency of different alleles.
What is the Hardy-Weinberg formula? - ANSWER p2 + 2pq + q2 = 1
Why do IgM antibodies, such as those formed against the ABO antigens, have the ability to
directly agglutinate red blood cells (RBCs) and cause visible agglutination? - ANSWER IgM
antibodies are larger molecules and have the ability to bind more antigen
3
, Which of the following enhancement mediums decreases the zeta potential, allowing anti-
body and antigen to come closer together? - ANSWER LISS.
LISS contains a reduced concentration of NaCl (0.2%) and results in a reduction in charged
ions within the ionic cloud, decreasing the zeta potential and facilitating antigen and anti-
body interaction.
This type of antibody response is analogous to an anamnestic antibody reaction. - AN-
SWER Secondary.
An anamnestic response is a secondary immune response in which memory lymphocytes re-
spond rapidly to foreign antigen in producing specific antibody. The antibodies are IgG and
are produced
at lower doses of antigen than in the primary response.
Which antibodies to a component of complement are contained in the rabbit polyspecific
antihuman globulin reagent for detection of in vivo sensitization? - ANSWER In the DAT
(direct antiglobulin test), rabbit
polyspecific antisera contains both an anti-human IgG component and an antibody against
the C3d component of complement.
Which of the following distinguishes A1 from A2 blood groups?
A. A2 antigen will not react with anti-A, A1 will
react strongly (4+)
B. An A2 person may form anti-A1; an A1 person
will not form anti-A1
C. An A1 person may form anti-A2, an A2 person
will not form anti-A1
D. A2 antigen will not react with anti-A from a nonimmunized donor; A1 will react with any
anti-A - ANSWER B. An A2 person may form anti-A1; an A1 person will not form anti-A1
A patient's serum is incompatible with O cells. The patient RBCs give a negative reaction to
anti-H lectin. What is the most likely cause of these results? - ANSWER Bombay is the
4
