What is the main cause of cancer?
A) DNA replication no longer working properly
B) Exposure to carcinogens in the environment
C) Old age, during which the cells of the body no longer work properly
D) We do not currently know the main cause of cancer.
B
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Hpv
A. can integrate into the host's chromosome. B. may be split into cancer-associated and wart-causing types. C. infections always lead to cancer. D. cannot infect newborns at birth. E. can integrate into the host's chromosome AND may be split into cancer-associated and wart-causing types
What would be a primary advantage of using an attenuated agent rather than just an antigen from that agent for a vaccine?
A. This is actually a disadvantage-it's much more dangerous to use an attenuated agent over a subunit (single antigen) vaccine due to the possibility of reversion of the microbe to a pathogenic state. B. An attenuated agent strongly stimulates ONLY the antibody production (humoral response) of the adaptive immune system. This provides the best and strongest long-term protection. C. An attenuated agent strongly stimulates ONLY the cytotoxic T cell (CTL, cell-mediated) side of the adaptive immune system. This provides the best and strongest long-term protection. D. An attenuated agent strongly stimulates both the humoral (antibody) AND cell-mediated (T cell) portions of the adaptive immune response, giving the best comprehensive long-term protection available.
The Nef protein helps HIV evade the adaptive immune system by
a. destroying cytotoxic T cells. b. destroying class I MHC proteins as soon as they get to the surface of infected cells. c. destroying class I MHC proteins in the cytoplasm. d. binding to class I MHC proteins at the cell surface, thereby blocking their availability to cytotoxic T cells. e. binding to class I MHC proteins in the cytoplasm, thereby preventing their transport to the cell surface.
Lymphocytes ignore which of the following in most
instances? a. cells coated with complement proteins b. cells with antigens on their surface c. “self” cells with MHC markers d. cells with both antigen and self-MHC markers e. cells with damaged or mutant self-MHC markers