WorksheetsBCR 1
Total questions: 15
Worksheet time: 36mins
X-ray crystallographic analysis revealed that immunoglobulin domains are folded into a characteristic compact structure called the immunoglobulin fold. Which of the following statement/s describes it
1. The α1 and α2 domains interact to form a platform of 2 eight antiparallel β strands spanned by two long α-helical regions.
2. structure consists of a “sandwich” of two β pleated sheets, each containing antiparallel β strands of amino acids, which are connected by loops of various lengths
3. The α3 domain and β2-microglobulin are organized into two β pleated sheets each formed by antiparallel β strands of amino acids.
4. The two β sheets within an immunoglobulin fold are stabilized by the hydrophobic interactions between them and by the conserved disulfide bond.
1, 2
1, 3 & 4
1 & 3
2& 4
Which of the following is not a BCR coreceptor?
a.TAPA
b.CD40
c.CR2
d. CD19
e. CD21
f.CD81
g. Iga/Igb
b, f and g
b and g
a, c and e
g
Which of the following Statements are False?
a.One of the remarkable properties of immune system is to directly recognise native antigens entering the system, this is attributed to BCR.
b.BCR is insufficient in transducing signals across membrane and needs the assistance of B cell coreceptor complex
c. It takes some time for the Humoral response to be activated, as the activation is dependent on the type of antigens entering the system
d. BCR is classified into Immunoglobulin superfamily because it does not contain a conserved 110 amino acid fold
e. the 1st heavy chain isotype to be secreted in an humoral response is IgG followed by IgM
a and c
c, d and e
b, d and e
d and e
Which of the following is a TCR co receptor?
alpha/beta
alpha/beta + gamma/epsilon, zetax2, delta/epsilon + CD4/CD8
alpha/beta + gamma/epsilon, zetax2, delta/epsilon
CD4/CD8
Which of the following Statements are False?
a.TCR recognises the peptides presented on MHC complex
b. TCR along with CD3 can recognize Antigens entering the system
c. the role of CD3 in the TCR is to ensure TCR recognises the peptide
d. CD4+ cells interact with MHC class 2 molecules
e. CD8+ cells interact with MHC class 1 molecules expressed by APC.
b, c and e
b and c
a, d and e
d and e
Which of the following is NOT a possible scenario when a pathogen has entered into blood stream?
Antigen-Macrophage>Tcell>Bcell>sIg>complement system> inflammation
Antigen-Tcell>Bcell> sIg>complement system> inflammation
Antigen-Bcell>Tcell>Bcell> sIg>complement system> inflammation
Antigen-Neutrophils>phagocytosis>Macrophage>>Tcell>Bcell>sIg>complement system> inflammation
A= VL, B= VH
A= CL, B = VL
A= VH, B= VL
A= CH, B=VH
What is the structural basis to the ability of Immunoglobulins to bind to infinite array of antigenic epitopes
presence of variable domain
presence of constant domain
presence of hypervariable region
presence of elbow and hinge
Distinct conserved regions within the variable domain are called as
(a)
Distinct regions of high variability within the variable domain are called as
(a)
Hypervariable regions coincide with antigen contact points
True
False
Antigen contact points in the Variable region are referred to as
Complementary regions
Complementary determining regions
Complementarity determining regions
Epitopes
Identify incorrect statement
The framework supports the variable domain
The framework forms a compact beta barrel/sandwich with a hydrophobic core
The hypervariable loops join, and are more flexible than, the beta strands
The hypervariable loops join, and are rigid than, the beta strands
Identify incorrect statement
The sequences of the hypervariable loops are highly variable amongst antibodies of different specificities
The variable sequences of the framework region influences the shape, hydrophobicity and charge at the tip of the antibody
Variable amino acid sequence in the hypervariable loops accounts for the diversity of antigens that can be recognised by a repertoire of antibodies
Identify Incorrect statement
Other g/d cells recognise lipids and glycoplipids from classical MHC molecules
g/d cells have mucosal localization
g/d T-cell clones appear to recognize self-generated Heat shock proteins or phosphoantigens derived from microbes.
g/d T cells are unconventional T lymphocytes
