Download MICROBIO320 Short Answers – These should be typically 1

MICROBIO320
Name______KEY_______________
Study Guide Questions - 15 pts total
Below are examples of the different types of questions that will be asked on Exam 1.
The only type of question not included in these examples is an essay question.
Short Answers – These should be typically 1-2 sentence answers.
1. Indicate two (2) reasons for increased life expectancy and indicate why they have resulted in
increased longevity. (1 pt) There are several acceptable answers including:
Vaccination
Improved hygiene
decreased infant mortality
Antibiotics
Better health care
decrease in unhealthy behavior
Improved sanitation
Better nutrition
and others were accepted
2. Name two functions attributed to complement activation. (1 pt)
Lysis of bacteria (and some viruses)
Increase in vascular permeability
Opsinization
Recruitment and activation of phagocytic cclls
3. Name two cell types of the myeloid lineage (1 pt)
Neutrophil
Dendritic cell
Eosinophil
Mast cell
Basophil
Macrophage
Matching – Each question is worth 0.5 pt
Choose the best answer from the following list: there may be more than 1 correct answer.
IgM
IgD
IgG
IgE
IgA
4. Best activator of the classical complement pathway. ___IgM and IgG (specifically IgG3)___
5. The LEAST abundant isotype found in serum. _______IgE_________
6. The secreted form is found in serum after an initial exposure to a pathogen. _IgM and IgG__
7. Plays a primary role in protecting against pathogens that infect through the respiratory and
gut mucosa. ____IgA_________
True / False – 1 pt each
8. __T___ The invariant chain occupies the MCH Class II binding groove until peptide is loaded
in the endosomal/ exocytic fusion vesicle.
9. __T__ Phagocytic cells participate in both the Innate and Adaptive immune responses.
10.__F__ Skin is the largest anatomical barrier (surface area) of our non-specific innate
immune defenses.
Multiple choice - Pick the best answer
Which of the following cells ARE NOT considered professional antigen presenting cells? (0.5 pt)
A.
B.
C.
D.
E.
B lymphocyctes (B cells)
Natural killer cells
Macrophage cells
Dendritic cells
All of the above
A term used when Ig molecules coat the surface of a microbe and enhances phagocytosis. (0.5 pt)
A.
B.
C.
D.
E.
Complement fixation
Neutralization
Opsonization
Endocytosis
All of the above
The antigen binding specificity of an antibody is due to: (0.5 pt)
A.
B.
C.
D.
E.
the constant regions of the light chains
the variable framework regions of the heavy & light chains
the variable regions of the heavy chains
the hypervariable regions of both heavy & light chains
All of the above
The following are considered humoral components of our non-specific Innate Immunity defense
(0.5 pt)
A.
B.
C.
D.
E.
Lysozyme.
Complement.
Sweat.
Defensins.
All of the above.
Which of the following statements is INCORRECT concerning antigen-specific receptors on B
cells? (0.5 pt)
A.
B.
C.
D.
E.
They are clonally distributed transmembrane molecules.
They have extensive cytoplasmic domains that interact with intracellular molecules.
They consist of polypeptides with variable and constant regions.
They are associated with signal transduction molecules at the cell surface.
They can interact with peptides derived from non-self antigens.
MHC class I molecules are important for which of the following? (0.5 pt)
A.
B.
C.
D.
E.
binding to CD8 molecules on T cells
presenting exogenous antigen (e.g., bacterial protein) to B cells
binding to Ig on B cells
binding to CD4 molecules on T cells
None of the above
Complete the following Diagram of B Cell DNA Gene rearrangement (4 pts)
The final Mature B cell will display IgA1 immunoglobulin with V3D1J2 specificity.
How many individual rearrangement steps will be required to produce this heavy chain?
Think about this!
Germline B Cell DNA
V1 V2 V3 V4 V5 V6
Vn
~40 V genes
D1 D2 D3 Dn J1 J2
~25 D genes
Jn
Cµ Cδ Cγ3 Cγ1 Cγ2 Cγ4 Cε Cα1 Cα2
6 J genes
Diagram the very first step in producing this immunoglobulin
Step 1: DJ rearrangement
D1 J2
Diagram Final mature B cell DNA structure.
V3D1J2 Cα1
How many steps will be required to produce this heavy chain?
Outline the steps if helpful – this way you might also get partial credit rather than just guessing
at the number.
Step 1: DJ rearrangement
Step 2: VDJ rearrangement
Step 3: primary transcript synthesized
Step 4: RNA processing to give rise to IgM (Constant mu region)
Step 5: Translation into protein
Step 6: Transport to ER and then secretion
Step 7: Class switching recombination event from IgM to IgA (constant regions)
I accepted answers that only highlighted the DNA rearrangement steps.