PSIO 431 IMMUNO UAZ QUESTIONS AND ANSWERS
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?
40
10,000
75
900 - CORRECT ANSWER✅✅900
Why is the quantity of IgE so low in the serum?
It binds immediately to Fc receptors on Mast cells
It is mostly found floating in the tissue fluids
It moves into the mucus membranes
It binds immediately to Fc receptors on neutrophils - CORRECT ANSWER✅✅It binds immediately to Fc
receptors on Mast cells
Which class of antibody has a valence of 10?
IgE
IgM
IgG
IgA - CORRECT ANSWER✅✅IgM
My preparation of IgG anti-Streptococcus, which used to agglutinate the bacteria very effectively, has
been tampered with by my evil graduate student! Now I find that what's in the tube binds specifically to
Streptococcus, but there is no agglutination! I think that what I have now is:
Fc
F(ab)2
Fab
Aged complement - CORRECT ANSWER✅✅Fab
,Lymphocytes are made to fit an antigen
Question 5 options:
True
False - CORRECT ANSWER✅✅False
Scientists are developing a new herpes vaccine. They should focus on part of the virus that is a good
___________.
Question 6 options:
Antigen
Mitogen
Epitope
Immunogen - CORRECT ANSWER✅✅Antigen
Although _____is the most effective at activating complement, ___________is the most abundant
serum immunoglobulin.
Question 7 options:
IgG; IgM
IgA; IgM
IgM; IgG
IgM; IgE - CORRECT ANSWER✅✅IgM; IgG
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?
There's no way to know based on the information above
Because of allotypic exclusion, it will be serine
Because of allotypic exclusion, it will be alanine
,Statistically, it's much more likely to be alanine - CORRECT ANSWER✅✅Because of allotypic exclusion, it
will be serine
Which of the following is the most sensitive test of antibody-antigen binding?
Question 9 options:
Precipitation
Hapten test
Lattice test
Agglutination - CORRECT ANSWER✅✅Agglutination
Dr. Jenner showed that vaccination with Cowpox protected people from Smallpox. What is that called?
Innoculation
Cross-Reaction
Clonal Selection
Somatic Hypermutation - CORRECT ANSWER✅✅Cross-Reaction
Got a 9/10 on these next 10 problems - CORRECT ANSWER✅✅
A fetus makes both IgM and IgG antibodies
Question 1 options:
True
False - CORRECT ANSWER✅✅False
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?
Question 2 options:
cytoplasmic delta chain
cytoplasmic mu chain
surface IgM
, surface IgD - CORRECT ANSWER✅✅cytoplasmic mu chain
At birth an infant has 200 units of IgG antibody against rubella per ML in his blood. He is not exposed to
rubella. At 9 weeks of age, what should the concentration be?
Question 3 options:
25 units
50 units
0 units, as he has not been exposed to the virus
100 units - CORRECT ANSWER✅✅25 units
Select the immunoglobulin class to which the statement best applies: (answers can be used more than
once) - CORRECT ANSWER✅✅Composed of 21 polypeptide chains IgM
The class of the antigen receptor found on the surface of mature B cells but NOT on immature B cells IgD
The class whose Fc portion binds to mast cells IgE
Clonal selection occurs in B and T lymphocytes
Question 5 options:
True
False - CORRECT ANSWER✅✅True
A routine sample of a newborn baby's blood is sent to the lab to be tested for antibody to
cytomegalovirus, which can cause serious developmental abnormalities in an infected fetus. The ward
clerk says the report has been called in as "positive" (there are antibodies that bind cytomegalovirus).
You think:
Question 7 options:
If it's IgM, I'll be worried
If it's IgG and IgM,I won't worry
If it's IgG, I'll suspect a lab error
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?
40
10,000
75
900 - CORRECT ANSWER✅✅900
Why is the quantity of IgE so low in the serum?
It binds immediately to Fc receptors on Mast cells
It is mostly found floating in the tissue fluids
It moves into the mucus membranes
It binds immediately to Fc receptors on neutrophils - CORRECT ANSWER✅✅It binds immediately to Fc
receptors on Mast cells
Which class of antibody has a valence of 10?
IgE
IgM
IgG
IgA - CORRECT ANSWER✅✅IgM
My preparation of IgG anti-Streptococcus, which used to agglutinate the bacteria very effectively, has
been tampered with by my evil graduate student! Now I find that what's in the tube binds specifically to
Streptococcus, but there is no agglutination! I think that what I have now is:
Fc
F(ab)2
Fab
Aged complement - CORRECT ANSWER✅✅Fab
,Lymphocytes are made to fit an antigen
Question 5 options:
True
False - CORRECT ANSWER✅✅False
Scientists are developing a new herpes vaccine. They should focus on part of the virus that is a good
___________.
Question 6 options:
Antigen
Mitogen
Epitope
Immunogen - CORRECT ANSWER✅✅Antigen
Although _____is the most effective at activating complement, ___________is the most abundant
serum immunoglobulin.
Question 7 options:
IgG; IgM
IgA; IgM
IgM; IgG
IgM; IgE - CORRECT ANSWER✅✅IgM; IgG
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?
There's no way to know based on the information above
Because of allotypic exclusion, it will be serine
Because of allotypic exclusion, it will be alanine
,Statistically, it's much more likely to be alanine - CORRECT ANSWER✅✅Because of allotypic exclusion, it
will be serine
Which of the following is the most sensitive test of antibody-antigen binding?
Question 9 options:
Precipitation
Hapten test
Lattice test
Agglutination - CORRECT ANSWER✅✅Agglutination
Dr. Jenner showed that vaccination with Cowpox protected people from Smallpox. What is that called?
Innoculation
Cross-Reaction
Clonal Selection
Somatic Hypermutation - CORRECT ANSWER✅✅Cross-Reaction
Got a 9/10 on these next 10 problems - CORRECT ANSWER✅✅
A fetus makes both IgM and IgG antibodies
Question 1 options:
True
False - CORRECT ANSWER✅✅False
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?
Question 2 options:
cytoplasmic delta chain
cytoplasmic mu chain
surface IgM
, surface IgD - CORRECT ANSWER✅✅cytoplasmic mu chain
At birth an infant has 200 units of IgG antibody against rubella per ML in his blood. He is not exposed to
rubella. At 9 weeks of age, what should the concentration be?
Question 3 options:
25 units
50 units
0 units, as he has not been exposed to the virus
100 units - CORRECT ANSWER✅✅25 units
Select the immunoglobulin class to which the statement best applies: (answers can be used more than
once) - CORRECT ANSWER✅✅Composed of 21 polypeptide chains IgM
The class of the antigen receptor found on the surface of mature B cells but NOT on immature B cells IgD
The class whose Fc portion binds to mast cells IgE
Clonal selection occurs in B and T lymphocytes
Question 5 options:
True
False - CORRECT ANSWER✅✅True
A routine sample of a newborn baby's blood is sent to the lab to be tested for antibody to
cytomegalovirus, which can cause serious developmental abnormalities in an infected fetus. The ward
clerk says the report has been called in as "positive" (there are antibodies that bind cytomegalovirus).
You think:
Question 7 options:
If it's IgM, I'll be worried
If it's IgG and IgM,I won't worry
If it's IgG, I'll suspect a lab error
