PSIO 431 IMMUNO UAZ EXAM
QUESTIONS COMPLETE WITH 100%
VERIFIED 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 - ANSWERS✔-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 - ANSWERS✔-It binds immediately to Fc
receptors on Mast cells
\.Which class of antibody has a valence of 10?
IgE
IgM
IgG
,IgA - ANSWERS✔-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 - ANSWERS✔-Fab
\.Lymphocytes are made to fit an antigen
Question 5 options:
True
False - ANSWERS✔-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 - ANSWERS✔-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 - ANSWERS✔-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 - ANSWERS✔-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 - ANSWERS✔-Agglutination
\.Dr. Jenner showed that vaccination with Cowpox protected people from Smallpox. What is
that called?
Innoculation
Cross-Reaction
, Clonal Selection
Somatic Hypermutation - ANSWERS✔-Cross-Reaction
\.A fetus makes both IgM and IgG antibodies
Question 1 options:
True
False - ANSWERS✔-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 - ANSWERS✔-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 - ANSWERS✔-25 units
\.Select the immunoglobulin class to which the statement best applies: (answers can be used
more than once) - ANSWERS✔-Composed of 21 polypeptide chains IgM
QUESTIONS COMPLETE WITH 100%
VERIFIED 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 - ANSWERS✔-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 - ANSWERS✔-It binds immediately to Fc
receptors on Mast cells
\.Which class of antibody has a valence of 10?
IgE
IgM
IgG
,IgA - ANSWERS✔-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 - ANSWERS✔-Fab
\.Lymphocytes are made to fit an antigen
Question 5 options:
True
False - ANSWERS✔-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 - ANSWERS✔-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 - ANSWERS✔-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 - ANSWERS✔-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 - ANSWERS✔-Agglutination
\.Dr. Jenner showed that vaccination with Cowpox protected people from Smallpox. What is
that called?
Innoculation
Cross-Reaction
, Clonal Selection
Somatic Hypermutation - ANSWERS✔-Cross-Reaction
\.A fetus makes both IgM and IgG antibodies
Question 1 options:
True
False - ANSWERS✔-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 - ANSWERS✔-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 - ANSWERS✔-25 units
\.Select the immunoglobulin class to which the statement best applies: (answers can be used
more than once) - ANSWERS✔-Composed of 21 polypeptide chains IgM
