I have to revise my exam. I have to explain why my answers where wrong, but I don\'t know why they are wrong. 1). Which of the following is NOT entirely a response of the innate immune system? My answer: Phagocytosis by macrophages Correct: Antibody mediated complement activation Why was my answer wrong? 2). Which of these characteristics are adaptive? My answer: Responds more quickly more quickly upon secondary exposure to pathogens. Correct: Response takes several days to develop, Responds more quickly upon secondary exposure to pathogens, and pathogen receptors are extremely varied. Why was my answer wrong? 3). What is the central mechanism for establishing self-tolerance? My answer: Immune cells that react to self-antigen are turned off when they recognize self- tissue. Correct: Self-reactive T cells and B cells are killed during development. Why was my answer wrong? 4). ____chemokine that recruits neutrophils and other immune cells to the site of infection. My answer: IL-12 Correct: IL-8 Why was my answer wrong? 5). Which cytokine is known for its anti-viral properties? My answer: TNF-alpha Correct: IFN-alpha Why was my answer wrong? 6). Which of the following effector T lymphocyte populations is produced via the activation of a naive T cell through antigen presented in MHC Class I? My answer: Th17 Correct: CTL Why was my answer wrong? 7). Superantigens are: My answer: None of these choices are correct Correct: bacterial toxins that activate T cells at a 100 times greater rate than other antigens. Why was my answer wrong? 8). Which of the following types of effector T lymphocytes is capable of inhibiting an immune response to an antigen recognized with its T-cell receptor (TCR)? My answer: Th2 Correct: Treg Why was my answer wrong? 9). An example of artificial passive immunity would be My answer: Chickenpox vaccine triggers extended immunity to chickenpox. Correct: giving a person immune serum globulins to chickenpox virus after exposure to the disease. Why was my answer wrong Solution 1). Which of the following is NOT entirely a response of the innate immune system? My answer: Phagocytosis by macrophages Correct: Antibody mediated complement activation Explination : simple antibody mediated response is a humoral immune sytem response which occurs after body makes antobody against any antigen after proper MHC antigen presentation.. and macrophages act as one of the antigen presenting cells ... hence antigen responses occur only after foreign substance is eaten by macrophage.... simply 2). Which of these characteristics are adaptive? My answer: Responds more quickly more quickly upon secondary exposure to pathogens. Correct: Response takes several days to develop, Responds more quickly upon secondary exposure to pathogens, and pathogen receptors are extremely . Explination : Adaptive immune resonse means forming an specific antibody against specific antigen and that occurs after antigen is presented by MHC and B-cell clonal expression occ.

1. I have to revise my exam. I have to explain why my answers where wrong, but I don't know
why they are wrong.
1). Which of the following is NOT entirely a response of the innate immune system?
My answer: Phagocytosis by macrophages
Correct: Antibody mediated complement activation
Why was my answer wrong?
2). Which of these characteristics are adaptive?
My answer: Responds more quickly more quickly upon secondary exposure to pathogens.
Correct: Response takes several days to develop, Responds more quickly upon secondary
exposure to pathogens, and pathogen receptors are extremely varied.
Why was my answer wrong?
3). What is the central mechanism for establishing self-tolerance?
My answer: Immune cells that react to self-antigen are turned off when they recognize self-
tissue.
Correct: Self-reactive T cells and B cells are killed during development.
Why was my answer wrong?
4). ____chemokine that recruits neutrophils and other immune cells to the site of infection.
My answer: IL-12
Correct: IL-8
Why was my answer wrong?
5). Which cytokine is known for its anti-viral properties?
My answer: TNF-alpha
Correct: IFN-alpha
Why was my answer wrong?
6). Which of the following effector T lymphocyte populations is produced via the activation of a
naive T cell through antigen presented in MHC Class I?
My answer: Th17
Correct: CTL
Why was my answer wrong?
7). Superantigens are:
My answer: None of these choices are correct
Correct: bacterial toxins that activate T cells at a 100 times greater rate than other antigens.
Why was my answer wrong?
8). Which of the following types of effector T lymphocytes is capable of inhibiting an immune
response to an antigen recognized with its T-cell receptor (TCR)?

2. My answer: Th2
Correct: Treg
Why was my answer wrong?
9). An example of artificial passive immunity would be
My answer: Chickenpox vaccine triggers extended immunity to chickenpox.
Correct: giving a person immune serum globulins to chickenpox virus after exposure to the
disease.
Why was my answer wrong
Solution
1). Which of the following is NOT entirely a response of the innate immune system?
My answer: Phagocytosis by macrophages
Correct: Antibody mediated complement activation
Explination : simple antibody mediated response is a humoral immune sytem response which
occurs after body makes antobody against any antigen after proper MHC antigen presentation..
and macrophages act as one of the antigen presenting cells ... hence antigen responses occur only
after foreign substance is eaten by macrophage.... simply
2). Which of these characteristics are adaptive?
My answer: Responds more quickly more quickly upon secondary exposure to pathogens.
Correct: Response takes several days to develop, Responds more quickly upon secondary
exposure to pathogens, and pathogen receptors are extremely .
Explination : Adaptive immune resonse means forming an specific antibody against specific
antigen and that occurs after antigen is presented by MHC and B-cell clonal expression occurs ..
which releases the specific antibody thereafter ... and it takes few days and is not quick .....
however on secondary exposure plasma contains memory Bcells which instantly recognises the
antigen thus primrary response is a bit delayed but secondary response is quick ...
3). What is the central mechanism for establishing self-tolerance?
My answer: Immune cells that react to self-antigen are turned off when they recognize self-
tissue.
Correct: Self-reactive T cells and B cells are killed during development.
EXPLINATION: Simple when immune cell reperotire is being formed in earllier stages of
development the cells which react to self antigens and can cause autoimmune problems are killed
thus only those cells are kept which react to only foreign antigens .... it is not cells are turned off
it is that cells dont exist there alltogether
4). ____chemokine that recruits neutrophils and other immune cells to the site of infection.

3. My answer: IL-12
Correct: IL-8
EXPLINATION: memory based question has no explination
SINCE I HAVE TO ANSWER ONLY 4 PARTS ACCORDING TO CHEGG
REQUIREMENTS BUT AS A COURTESY PART I WILL TRY TO ANSWER THE REST
TOO
5). Which cytokine is known for its anti-viral properties?
My answer: TNF-alpha
Correct: IFN-alpha
EXPLINATION: memory based question has no explination
6). Which of the following effector T lymphocyte populations is produced via the activation of a
naive T cell through antigen presented in MHC Class I?
My answer: Th17
Correct: CTL
EXPLINATION :MHC CLASS 1 antigen presentation produces cytotoxic T lymphocytes
releasing proteases andother killing factors which could kill virus infected cells ...where as MHC
CLASS II antigen presentation forms specific antibody forms B cells.
7). Superantigens are:
My answer: None of these choices are correct
Correct: bacterial toxins that activate T cells at a 100 times greater rate than other antigens.
EXPLINATION: memory based question .. stil superantigens can cause whole body inflamation
in a process called anaphylaxis and septic shock syndrome ..
8). Which of the following types of effector T lymphocytes is capable of inhibiting an immune
response to an antigen recognized with its T-cell receptor (TCR)?
My answer: Th2
Correct: Treg
Explintation: Memory based question...
9). An example of artificial passive immunity would be
My answer: Chickenpox vaccine triggers extended immunity to chickenpox.
Correct: giving a person immune serum globulins to chickenpox virus after exposure to the
disease.
Explination: attenuated viruses contain protien fragments from virus hence body produces
antibodies against them and memory cells remain which act quick in case of secondary
chickenpox infection