WITH REVISED ANSWERS –
UPDATED!!!
How do complements work? - Answer-circulate in blood, inactive, if activated:
increased inflammation of local cells
enhanced phagocytosis or
formation of channel forming complex called membrane attack complex (causes lysis of
pathogen), effective against gram negative bacteria (it can pierce outer membrane
Distinguish between the different methods natural killer cells use to destroy their cell
targets - Answer-kill cells by secret apoptosis inducing proteins,
adaptive immunity - antibodies for antigens
passive immunity - activation of target cell receptors that trigger death
Distinguish between the prongs of adaptive immune response - Answer-humoral, cell
immunity
What are the key processes in alerting the adaptive immune system? - Answer-
inflammation - flood area with cytokines and chemokines (attract/activate phagocytes)
macrophages and dendritic cells phagocytose pathogens and display antigens on their
surface to lymphocytes
What are the pathways of stimulating the lymphocytes? - Answer-exposed to antigens:
B-cells make specific antibodies, T-cells develop into Cytotoxic lymphocytes which
killing pathogenic (associated) cells, some cells mature to memory B/T-cells,
What are lymphocytes - Answer-white blood cells that mature into b or t cells
What happens when an Ab binds an Ag - Answer-precipitation - bind multiple Ags to
form large insoluble complexes
neutralization - binding causes pathogens to struggle to adhere to be uptook
complement fixation - binding signals complement pathways
agglutination - crosslink many pathogens to form large molecule trapped to be
phagocytosed
How do cytotoxic t-cells function? - Answer-t-cell activated,
, matures into a CTL,
antigen specific receptor placed on surface,
infected cell has protein on surface: Major Histocompatibility complex,
if receptor matches t-cell antigen cells bind,
CTL secretes enzymes which cause cell to lyse,
remains are phagocytosed
What are the differences between eukaryotic microbes, archea, bacteria and viruses? -
Answer-genome size: viruses (smallest), archaea, bacteria, eurkayotes
What are bacteriophages? - Answer-viruses that infect bacteria
What is a virus? - Answer-Infectious, obligate intracellular parasite that is 100%
dependent on host to replicate: enters a host and uses host machinery to replicate
What are examples of viruses that infect prokaryotes? - Answer-vaccinia virus,
herpesvirus, rhadovirus, mimivirus, human papillovirus, tobacco mosaic virus
What are examples of viruses that infect eukaryotes? - Answer-flexous-tailed phage,
X174 phage, bacteriophage
What are the differences between the structures of phages? - Answer-tailed - 10^21 on
earth, more than all other organisms combined
P22 - lost its tail: infects salmonella
M13 - 2700 copies of gp8 protein make up capsid
What are the differences in structure of a enveloped and non-enveloped viruses? -
Answer-nonenveloped - capsid (helical/icosahedral) made of protein assembled around
a nucleic acid
enveloped - lipid/carbohydrate membrane around capsid w/ viral proteins
What distinguishes the five steps of the bacteriophage assembly line in lytic infections?
- Answer-infection - attaches to surface of cell and injects its genetic material
replication - replicates genetic info using host machinery
production of viral proteins - host machinery makes parts of new phages
assembly - new phages are assembled from parts