IMM250 Final UPDATED ACTUAL
Questions and CORRECT Answers
How do barriers defend against infection? - CORRECT ANSWER- ✔✔Physically and
mechanically keep pathogens out. Example: stomach and skin. They do not need to go
through a process to get activated; they are immediately active.
Summarize innate immunity? - CORRECT ANSWER- ✔✔It involves cells and molecules
that get recruited to the site of infection. Innate cells recognize PAMPs using PRRs. PAMPs
are common to a certain group of pathogens.
Summarize adaptive immunity? - CORRECT ANSWER- ✔✔It involves cells and molecules
that get recruited to the site of infection. Lymphocytes are the ones used in the adaptive
response. They recognize antigens by using antigen receptors.
What is an antigen? - CORRECT ANSWER- ✔✔A macromolecule that is specific to one
pathogen. They are recognized during the adaptive immune response.
What is an epitope? - CORRECT ANSWER- ✔✔A small area of the antigen that is bound by
the surface antigen receptor on the tip of an antibody.
What mechanism do B cells use to recognize a threat? - CORRECT ANSWER- ✔✔Epitope
binding to antibodies.
What mechanism do T cells use to recognize a threat? - CORRECT ANSWER- ✔✔A small
protein piece of the antigen is held up to the T cell receptors. The epitope is presented to the
receptor on the T cell by an MHC molecule.
What is an MHC molecule? - CORRECT ANSWER- ✔✔It is a special antigen presenting
cell that helps T cells recognize a threat.
What kinds of threats do B cells assist with? - CORRECT ANSWER- ✔✔Extracellular
threats. They block entry into cells and tag pathogens for destruction by secreting antibodies.
,What kind of threats do cytotoxic T cells help with? - CORRECT ANSWER-
✔✔Intracellular threats. These cells are useful for when a pathogen gets past the B cell's
response. They kill cells that have been completely infected in order to prevent the spread of
a disease.
What kind of help do helper T cells do? - CORRECT ANSWER- ✔✔They provide overall
help and defence by secreting cytokines required for the activation of B, Tc, and other innate
leukocytes.
How to B cells and T cells have such diverse functionality when humans only have 25,000
genes? - CORRECT ANSWER- ✔✔Gene rearrangement: the B cell receptor and T cell
receptor genes consist of many small segments arranged into one big exon. The small
segments can rearrange themselves to create any possible combinations. This means that
there can be a huge variety of proteins that can be created within a small population of B cells
or T cells.
What does the B cell receptor look like? - CORRECT ANSWER- ✔✔There are 2 identical
antigen binding sites. Both of the light chains on the receptor are encoded by the same IgL
gene. Both of the heavy chains are encoded by the same IgH gene.
What does a T cell receptor look like? - CORRECT ANSWER- ✔✔It has 1 antigen binding
site. It still has 2 different chains: an alpha chain encoded by the TCR alpha gene and a beta
chain encoded by the TCR beta gene.
What are V domains? - CORRECT ANSWER- ✔✔These are the top area of the B cell
receptor and T cell receptors. They facilitate recognition of a diverse variety of antigens.
They have high structural variability.
What are C domains? - CORRECT ANSWER- ✔✔These are the bottom areas of the B cell
receptor and T cell receptors. They facilitate common functions like signal transduction and
clearance.
What are complementarity determining (CDR) regions? - CORRECT ANSWER- ✔✔These
regions are right at the tip of the antigen receptors on B cells and T cells. They are hotspots of
protein variability.
, What is VDJ recombination? - CORRECT ANSWER- ✔✔The unique mechanism of genetic
recombination that occurs in B cell and T cell maturation. It results in a high diversity of
antibodies and receptors. It is exclusive to lymphocytes of the adaptive system.
What is the Thyroid? - CORRECT ANSWER- ✔✔A gland in the neck that responds to
hormones from the pituitary gland.
What happens if the TSH receptor is blocked by an antibody? - CORRECT ANSWER-
✔✔There is decreased thyroid hormone secretion which leads to fatigue, weight gain, and
hair loss. Also known as hypothyroidism of Hashimomoto's disease.
What happens if an antibody binds to the TSH receptor? - CORRECT ANSWER-
✔✔Epithelial cells will mistake the antibody for TSH and produce overwhelming amounts of
the thyroid hormone. This leads to weight loss, sweating, and rapid heart rate. Also known as
hyperthyroidism or Grave's disease.
What are naive lymphocytes? - CORRECT ANSWER- ✔✔Lymphocytes that have never
encountered an antigen before.
What is clonal selection? - CORRECT ANSWER- ✔✔The process of growth and division of
immune cells so that they can respond to threats better and more specifically.
What are effector cells? - CORRECT ANSWER- ✔✔Short lived cells that act quickly to
eliminate pathogens.
What are memory cells? - CORRECT ANSWER- ✔✔Long lived cells that respond to the
same pathogen if encountered later on in time. This kind of response is why survivors of
infection gain immunity to a disease. It is also why vaccines are effective.
What is Leukemia? - CORRECT ANSWER- ✔✔A type of cancer that involves a
hematopoietic cell in the bone marrow becoming malignant. The progeny cells spill out into
the blood. It is also known as "liquid malignancy."
Questions and CORRECT Answers
How do barriers defend against infection? - CORRECT ANSWER- ✔✔Physically and
mechanically keep pathogens out. Example: stomach and skin. They do not need to go
through a process to get activated; they are immediately active.
Summarize innate immunity? - CORRECT ANSWER- ✔✔It involves cells and molecules
that get recruited to the site of infection. Innate cells recognize PAMPs using PRRs. PAMPs
are common to a certain group of pathogens.
Summarize adaptive immunity? - CORRECT ANSWER- ✔✔It involves cells and molecules
that get recruited to the site of infection. Lymphocytes are the ones used in the adaptive
response. They recognize antigens by using antigen receptors.
What is an antigen? - CORRECT ANSWER- ✔✔A macromolecule that is specific to one
pathogen. They are recognized during the adaptive immune response.
What is an epitope? - CORRECT ANSWER- ✔✔A small area of the antigen that is bound by
the surface antigen receptor on the tip of an antibody.
What mechanism do B cells use to recognize a threat? - CORRECT ANSWER- ✔✔Epitope
binding to antibodies.
What mechanism do T cells use to recognize a threat? - CORRECT ANSWER- ✔✔A small
protein piece of the antigen is held up to the T cell receptors. The epitope is presented to the
receptor on the T cell by an MHC molecule.
What is an MHC molecule? - CORRECT ANSWER- ✔✔It is a special antigen presenting
cell that helps T cells recognize a threat.
What kinds of threats do B cells assist with? - CORRECT ANSWER- ✔✔Extracellular
threats. They block entry into cells and tag pathogens for destruction by secreting antibodies.
,What kind of threats do cytotoxic T cells help with? - CORRECT ANSWER-
✔✔Intracellular threats. These cells are useful for when a pathogen gets past the B cell's
response. They kill cells that have been completely infected in order to prevent the spread of
a disease.
What kind of help do helper T cells do? - CORRECT ANSWER- ✔✔They provide overall
help and defence by secreting cytokines required for the activation of B, Tc, and other innate
leukocytes.
How to B cells and T cells have such diverse functionality when humans only have 25,000
genes? - CORRECT ANSWER- ✔✔Gene rearrangement: the B cell receptor and T cell
receptor genes consist of many small segments arranged into one big exon. The small
segments can rearrange themselves to create any possible combinations. This means that
there can be a huge variety of proteins that can be created within a small population of B cells
or T cells.
What does the B cell receptor look like? - CORRECT ANSWER- ✔✔There are 2 identical
antigen binding sites. Both of the light chains on the receptor are encoded by the same IgL
gene. Both of the heavy chains are encoded by the same IgH gene.
What does a T cell receptor look like? - CORRECT ANSWER- ✔✔It has 1 antigen binding
site. It still has 2 different chains: an alpha chain encoded by the TCR alpha gene and a beta
chain encoded by the TCR beta gene.
What are V domains? - CORRECT ANSWER- ✔✔These are the top area of the B cell
receptor and T cell receptors. They facilitate recognition of a diverse variety of antigens.
They have high structural variability.
What are C domains? - CORRECT ANSWER- ✔✔These are the bottom areas of the B cell
receptor and T cell receptors. They facilitate common functions like signal transduction and
clearance.
What are complementarity determining (CDR) regions? - CORRECT ANSWER- ✔✔These
regions are right at the tip of the antigen receptors on B cells and T cells. They are hotspots of
protein variability.
, What is VDJ recombination? - CORRECT ANSWER- ✔✔The unique mechanism of genetic
recombination that occurs in B cell and T cell maturation. It results in a high diversity of
antibodies and receptors. It is exclusive to lymphocytes of the adaptive system.
What is the Thyroid? - CORRECT ANSWER- ✔✔A gland in the neck that responds to
hormones from the pituitary gland.
What happens if the TSH receptor is blocked by an antibody? - CORRECT ANSWER-
✔✔There is decreased thyroid hormone secretion which leads to fatigue, weight gain, and
hair loss. Also known as hypothyroidism of Hashimomoto's disease.
What happens if an antibody binds to the TSH receptor? - CORRECT ANSWER-
✔✔Epithelial cells will mistake the antibody for TSH and produce overwhelming amounts of
the thyroid hormone. This leads to weight loss, sweating, and rapid heart rate. Also known as
hyperthyroidism or Grave's disease.
What are naive lymphocytes? - CORRECT ANSWER- ✔✔Lymphocytes that have never
encountered an antigen before.
What is clonal selection? - CORRECT ANSWER- ✔✔The process of growth and division of
immune cells so that they can respond to threats better and more specifically.
What are effector cells? - CORRECT ANSWER- ✔✔Short lived cells that act quickly to
eliminate pathogens.
What are memory cells? - CORRECT ANSWER- ✔✔Long lived cells that respond to the
same pathogen if encountered later on in time. This kind of response is why survivors of
infection gain immunity to a disease. It is also why vaccines are effective.
What is Leukemia? - CORRECT ANSWER- ✔✔A type of cancer that involves a
hematopoietic cell in the bone marrow becoming malignant. The progeny cells spill out into
the blood. It is also known as "liquid malignancy."
