BLD204 EXAM 2 QUESTIONS AND ANSWERS WITH
COMPLETE SOLUTIONS GRADED A++ LATEST UPDATE
GRADED A++
Differentiate between a humoral and cellular immune response based on cell type
and rate of response to antigen challenge
Define antigen and antibody
Antigen: molecules recognized as "non-self"
- > capable of inducing an immune response
-> just one part is recognized, the epitope
-> 2 types:
1. Endogenous (native to host)
2. Exogenous (environmental)
Antibody: also known as immunoglobins (Ig)
-> agglutinate (stick to) and lyse bacteria
-> opsonize bacteria
-> initiate classical complement pathway
-> neutralize toxins
-> block microbe entry into tissues
-> assist in killing infected cells
*not all classes do these*
,Describe the function of macrophages and other APCs in immune responses
Antigen Presenting Cells (APCS): capture and display the Ag "flag"
-> 3 types:
1. DC dendritic cells: capture and present antigens to T cells
-> express MHC II and T cell costimulatory molecules
-> found in the T cell zones in lymphoid tissue
2. Macrophages: phagocytize and present antigen
3. B cells: recognize antigen via BCR, take it in and process it, present via MHC II
molecules to helper Ts
List and describe the two classes of MHC molecules based on their structure,
tissue distribution, and function
MHC stands for Major Histocompatibility Complex
-> Two classes:
1. MHC Class I: present on nucleated cells
-> signal to CD8+ cytotoxic Ts
-> Heavy alpha chain and B2-microglobulin chain
2. MHC Class II: present on professional APCs
-> antigen is consumed, processed and presented in MHC II by these cells
-> two peptide chains of more equal size
-> signal recognized by CD4+ helper Ts
List and describe the five different classes of antibodies and the function of each
1. IgG
-> 70-80% of plasma Ig
, -> neutralizes toxins and opsonizes bacteria
-> only class that crosses placenta, protection for fetus from mom
2. IgM
-> largest, pentamer, snowflake looking
-> 10 binding sites, good for repeating epitopes
-> first after immunization
3. IgA
-> mucosa, tears, sweat, bile, breast milk
-> stops bacteria and viruses from entering epithelium
4. IgE
-> Fc fragments binds to receptors on mast cells
-> Ag-binding results in release of granules (histamine, leukotrienes) and calls
eosinophils
-> parasite infections
-> involved in hypersensitivity
5. IgD
-> present on some B cells
-> helps with antigen recognition/activation along with IgM
-> secreted IgD helps arm some basophils and mast cells in mucosa to help w/ immune
surveillance
Differentiate between primary and secondary lymphoid tissue
Primary: cells differentiate and mature into lymphocytes here
-> thymus, bone marrow
COMPLETE SOLUTIONS GRADED A++ LATEST UPDATE
GRADED A++
Differentiate between a humoral and cellular immune response based on cell type
and rate of response to antigen challenge
Define antigen and antibody
Antigen: molecules recognized as "non-self"
- > capable of inducing an immune response
-> just one part is recognized, the epitope
-> 2 types:
1. Endogenous (native to host)
2. Exogenous (environmental)
Antibody: also known as immunoglobins (Ig)
-> agglutinate (stick to) and lyse bacteria
-> opsonize bacteria
-> initiate classical complement pathway
-> neutralize toxins
-> block microbe entry into tissues
-> assist in killing infected cells
*not all classes do these*
,Describe the function of macrophages and other APCs in immune responses
Antigen Presenting Cells (APCS): capture and display the Ag "flag"
-> 3 types:
1. DC dendritic cells: capture and present antigens to T cells
-> express MHC II and T cell costimulatory molecules
-> found in the T cell zones in lymphoid tissue
2. Macrophages: phagocytize and present antigen
3. B cells: recognize antigen via BCR, take it in and process it, present via MHC II
molecules to helper Ts
List and describe the two classes of MHC molecules based on their structure,
tissue distribution, and function
MHC stands for Major Histocompatibility Complex
-> Two classes:
1. MHC Class I: present on nucleated cells
-> signal to CD8+ cytotoxic Ts
-> Heavy alpha chain and B2-microglobulin chain
2. MHC Class II: present on professional APCs
-> antigen is consumed, processed and presented in MHC II by these cells
-> two peptide chains of more equal size
-> signal recognized by CD4+ helper Ts
List and describe the five different classes of antibodies and the function of each
1. IgG
-> 70-80% of plasma Ig
, -> neutralizes toxins and opsonizes bacteria
-> only class that crosses placenta, protection for fetus from mom
2. IgM
-> largest, pentamer, snowflake looking
-> 10 binding sites, good for repeating epitopes
-> first after immunization
3. IgA
-> mucosa, tears, sweat, bile, breast milk
-> stops bacteria and viruses from entering epithelium
4. IgE
-> Fc fragments binds to receptors on mast cells
-> Ag-binding results in release of granules (histamine, leukotrienes) and calls
eosinophils
-> parasite infections
-> involved in hypersensitivity
5. IgD
-> present on some B cells
-> helps with antigen recognition/activation along with IgM
-> secreted IgD helps arm some basophils and mast cells in mucosa to help w/ immune
surveillance
Differentiate between primary and secondary lymphoid tissue
Primary: cells differentiate and mature into lymphocytes here
-> thymus, bone marrow
