PSIO 431: EXAM REVIEW UPDATED ACTUAL
QUESTIONS AND CORRECT ANSWERS
Question:
1. A new species of rodent is found on a tiny island. Genetic analysis shows that it is fully inbred.
When its immunoglobulin genes are examined, its H chain region shows 4 V, 3 D and 5 J segments. It
has no lambda light chains, only kappa; they have 5 V, and 3 J (there are no D regions in light chains).
So, ignoring any somatic mechanisms except V(D)J recombination, the germ line alone predicts that
this animal could make how many antibodies?
Answer:
900
Question:
2. Monocytes and B cells arise from ________________
Answer:
Lymphoid stem cells
Question:
3. What mechanism allows for simultaneous surface expression of both IgM and IgD at the same time
on the same B cell?
Answer:
Alternative RNA splicing
Question:
4. What antibody is secreted first during primary (first exposure) B cell responses to antigen?
Answer:
IgM
Question:
5. Select the immunoglobulin class to which the statement best applies: (answers can be used more
than once)
--3--Composed of 21 polypeptide chains
--2--The class of the antigen receptor found on the surface of mature B cells but NOT on immature B
cells
--5--The class whose Fc portion binds to mast cells
Answer:
1.IgD
2.IgM
3.IgG
4.IgA (complete secreted form)
5.IgE
Question:
6. Which shows a typical order for the appearance of serum antibody isotopes following
immunization?
Answer:
IgG,IgM,IgE
, Question:
7. The complement system is involved in______________.
Answer:
Killing bacteria by attacking their membranes directly
Question:
8. I isolated a single plasma cell that was secreting IgG, and sequenced a single H chain (new
technology allows this with 100% accuracy). At the position in this image shown by the arrow, on the
Fc part of the H chain, I found the amino acid serine. That was a surprise, as almost all humans have
alanine at that position. I asked an expert in my department what the amino acid in the exact same
position on the other H chain in this particular molecule would be. What was the expert response?
Answer:
Because of allotypic exclusion, it will be alanine
Question:
9. Scientists are developing a new herpes vaccine. They should focus on part of the virus that is a good
___________.
Answer:
Antigen
Question:
10. I have a sample of cells from the bone marrow. What would be the first "sign" that the cell I'm
looking at is going to be a B cell?
Answer:
cytoplasmic delta chain
Question:
11. Which class of antibody is made up of 10 polypeptide chains? Question 1 options: IgD IgA IgM
IgE IgG
Answer:
IgM
Question:
12. The Fc component of antibody is important for all EX- CEPT: Question 2 options: Complement
binding Mast cell degranulation Antigen binding Phagocyte binding
Answer:
Mast cell degranulation
Question:
13. What is the name given to the amino acids of an antibody that directly contact the antigen?
Question 3 options: Immunogen Complementarity-determining region Antigenic determinant
Pattern-recognition receptors
Answer:
Complementarity-determining region
Question:
14. Where, on IgG molecules, will you find Constant Domains? Question 4 options: Only on H chains
On both L and H chains Only on L chains Only in the Fc portion
QUESTIONS AND CORRECT ANSWERS
Question:
1. A new species of rodent is found on a tiny island. Genetic analysis shows that it is fully inbred.
When its immunoglobulin genes are examined, its H chain region shows 4 V, 3 D and 5 J segments. It
has no lambda light chains, only kappa; they have 5 V, and 3 J (there are no D regions in light chains).
So, ignoring any somatic mechanisms except V(D)J recombination, the germ line alone predicts that
this animal could make how many antibodies?
Answer:
900
Question:
2. Monocytes and B cells arise from ________________
Answer:
Lymphoid stem cells
Question:
3. What mechanism allows for simultaneous surface expression of both IgM and IgD at the same time
on the same B cell?
Answer:
Alternative RNA splicing
Question:
4. What antibody is secreted first during primary (first exposure) B cell responses to antigen?
Answer:
IgM
Question:
5. Select the immunoglobulin class to which the statement best applies: (answers can be used more
than once)
--3--Composed of 21 polypeptide chains
--2--The class of the antigen receptor found on the surface of mature B cells but NOT on immature B
cells
--5--The class whose Fc portion binds to mast cells
Answer:
1.IgD
2.IgM
3.IgG
4.IgA (complete secreted form)
5.IgE
Question:
6. Which shows a typical order for the appearance of serum antibody isotopes following
immunization?
Answer:
IgG,IgM,IgE
, Question:
7. The complement system is involved in______________.
Answer:
Killing bacteria by attacking their membranes directly
Question:
8. I isolated a single plasma cell that was secreting IgG, and sequenced a single H chain (new
technology allows this with 100% accuracy). At the position in this image shown by the arrow, on the
Fc part of the H chain, I found the amino acid serine. That was a surprise, as almost all humans have
alanine at that position. I asked an expert in my department what the amino acid in the exact same
position on the other H chain in this particular molecule would be. What was the expert response?
Answer:
Because of allotypic exclusion, it will be alanine
Question:
9. Scientists are developing a new herpes vaccine. They should focus on part of the virus that is a good
___________.
Answer:
Antigen
Question:
10. I have a sample of cells from the bone marrow. What would be the first "sign" that the cell I'm
looking at is going to be a B cell?
Answer:
cytoplasmic delta chain
Question:
11. Which class of antibody is made up of 10 polypeptide chains? Question 1 options: IgD IgA IgM
IgE IgG
Answer:
IgM
Question:
12. The Fc component of antibody is important for all EX- CEPT: Question 2 options: Complement
binding Mast cell degranulation Antigen binding Phagocyte binding
Answer:
Mast cell degranulation
Question:
13. What is the name given to the amino acids of an antibody that directly contact the antigen?
Question 3 options: Immunogen Complementarity-determining region Antigenic determinant
Pattern-recognition receptors
Answer:
Complementarity-determining region
Question:
14. Where, on IgG molecules, will you find Constant Domains? Question 4 options: Only on H chains
On both L and H chains Only on L chains Only in the Fc portion
