ABO ADVANCED FORMULAS PRACTICE EXAMINATION
Questions with Correct Answers (Grade A+)
Question 1: Forward Type.
Answer: Looking for unknown antigen on RBC, use known antibody (Antisera), Agglutination indicates the
presence of antigen, determines the ABO group
Question 2: Which of the following shows ABO frequencies from most common to least common?
A. A > O > AB > B
B. AB > A > B > O
C. B > AB > A > O
D. A > B > AB > O
E. O > A > B > AB.
Answer: e. O > A > B > AB
Question 3: What antibody class are ABO antibodies primarily?
A. IgA
B. IgE
C. IgG
D. IgM.
Answer: IgM
Question 4: All of the following (a-d) would be classified as natural occurring antibodies (produced
from “look alike antigens” in the environment and not from foreign red blood cell exposure) except:
A. Anti-A
B. Anti-B
C. Anti-A,B
D. Anti-D
E. All of the above (a-d) would be classified as natural occurring antibodies.
Answer: Anti-D
Question 5: Which of the following would be considered Codominant?
A. AO
B. AB
C. A1A2
D. Dd.
Answer: AB
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,Question 6: Which would be considered a heterozygous expression?
A. OO
B. ee
C. cE
D. Cc.
Answer: Cc
Question 7: Reverse Type.
Answer: Use Known antigen (reagent red cells) to detect--Unknown antibody in plasma, agglutination
indicates the presence of antibody, confirms the ABO group (most of the time, ~2% discrepancy)
Question 8: Which one of the following is considered recessive?
A. A1
B. A2
C. c
D. S
E.
Answer: A2
Question 9: ABO subgroups: "A" main subgroups.
Answer: Type "A" may be broken down into 2 main subgroups: A1 and A2
Question 10: 3+ agglutination appears as:
A. One large solid agglutinate with a clear background
B. Very fine agglutinates with a red background
C. Several large clumps with a clear background
D. Several small-medium sized agglutinates with a clear background
E. Complete hemolysis is seen (with no agglutinates).
Answer: Several large clumps with a clear background
Question 11: What % of A people have an unexpected reverse reaction that doesn't match forward
reaction.
Answer: 1% of the 40% that are type A
Question 12: A1 phenotype has which antigens.
Answer: A1 and A (H)
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, Question 13: A2 phenotype has which antigens.
Answer: A only (NO such thing as A2 antigen) (H)
Question 14: 1+ agglutination appears as:
A. One large solid agglutinate with a clear background
B. Very fine agglutinates with a red background
C. Several large clumps with a clear background
D. Several small-medium sized agglutinates with a clear background
E. Complete hemolysis is seen (with no agglutinates).
Answer: Very fine agglutinates with a red background
Question 15: If the Father's type (phenotype) was AB and the Mother's type was B, what would be the
possible genotypes of their offspring? (Not including any subgroups).
A. AA, AO, BB, BO
B. AB, AA, BB, AO
C. AB, AO, BB, BO
D. AO, AA, BO, OO.
Answer: AB, AO, BB, BO
Question 16: Quantitative A1 v. A2: A1.
Answer: A1 has higher concentration of A (in addition to having A1 antigen)
Question 17: If the Father's type (phenotype) was AB and the Mother's type was A, what would be the
possible genotypes of their offspring? (Include A2 subgroups).
A. A1B, A1A1, A2B, A2O, BB, BO
B. A1B, A2B, A1A2, A1O, A2O, BO, OO
C. A1B, A2B, A1A2, A2A2, BO, A1O, A2O, OO
D. A1B, A2B, A1A1, A1A2, A1O, A2O, A2A2, BO.
Answer:
1. A1B
2. A2B
3. A1A1
4. A1A2
5. A1O
6. A2O
7. A2A2
8. BO
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Questions with Correct Answers (Grade A+)
Question 1: Forward Type.
Answer: Looking for unknown antigen on RBC, use known antibody (Antisera), Agglutination indicates the
presence of antigen, determines the ABO group
Question 2: Which of the following shows ABO frequencies from most common to least common?
A. A > O > AB > B
B. AB > A > B > O
C. B > AB > A > O
D. A > B > AB > O
E. O > A > B > AB.
Answer: e. O > A > B > AB
Question 3: What antibody class are ABO antibodies primarily?
A. IgA
B. IgE
C. IgG
D. IgM.
Answer: IgM
Question 4: All of the following (a-d) would be classified as natural occurring antibodies (produced
from “look alike antigens” in the environment and not from foreign red blood cell exposure) except:
A. Anti-A
B. Anti-B
C. Anti-A,B
D. Anti-D
E. All of the above (a-d) would be classified as natural occurring antibodies.
Answer: Anti-D
Question 5: Which of the following would be considered Codominant?
A. AO
B. AB
C. A1A2
D. Dd.
Answer: AB
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,Question 6: Which would be considered a heterozygous expression?
A. OO
B. ee
C. cE
D. Cc.
Answer: Cc
Question 7: Reverse Type.
Answer: Use Known antigen (reagent red cells) to detect--Unknown antibody in plasma, agglutination
indicates the presence of antibody, confirms the ABO group (most of the time, ~2% discrepancy)
Question 8: Which one of the following is considered recessive?
A. A1
B. A2
C. c
D. S
E.
Answer: A2
Question 9: ABO subgroups: "A" main subgroups.
Answer: Type "A" may be broken down into 2 main subgroups: A1 and A2
Question 10: 3+ agglutination appears as:
A. One large solid agglutinate with a clear background
B. Very fine agglutinates with a red background
C. Several large clumps with a clear background
D. Several small-medium sized agglutinates with a clear background
E. Complete hemolysis is seen (with no agglutinates).
Answer: Several large clumps with a clear background
Question 11: What % of A people have an unexpected reverse reaction that doesn't match forward
reaction.
Answer: 1% of the 40% that are type A
Question 12: A1 phenotype has which antigens.
Answer: A1 and A (H)
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, Question 13: A2 phenotype has which antigens.
Answer: A only (NO such thing as A2 antigen) (H)
Question 14: 1+ agglutination appears as:
A. One large solid agglutinate with a clear background
B. Very fine agglutinates with a red background
C. Several large clumps with a clear background
D. Several small-medium sized agglutinates with a clear background
E. Complete hemolysis is seen (with no agglutinates).
Answer: Very fine agglutinates with a red background
Question 15: If the Father's type (phenotype) was AB and the Mother's type was B, what would be the
possible genotypes of their offspring? (Not including any subgroups).
A. AA, AO, BB, BO
B. AB, AA, BB, AO
C. AB, AO, BB, BO
D. AO, AA, BO, OO.
Answer: AB, AO, BB, BO
Question 16: Quantitative A1 v. A2: A1.
Answer: A1 has higher concentration of A (in addition to having A1 antigen)
Question 17: If the Father's type (phenotype) was AB and the Mother's type was A, what would be the
possible genotypes of their offspring? (Include A2 subgroups).
A. A1B, A1A1, A2B, A2O, BB, BO
B. A1B, A2B, A1A2, A1O, A2O, BO, OO
C. A1B, A2B, A1A2, A2A2, BO, A1O, A2O, OO
D. A1B, A2B, A1A1, A1A2, A1O, A2O, A2A2, BO.
Answer:
1. A1B
2. A2B
3. A1A1
4. A1A2
5. A1O
6. A2O
7. A2A2
8. BO
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