The A subunit has toxic (enzymatic) activity.
B subunit binds to surface of host human cell and facilitates internalization of the A sub
unit
/.Adaptation of oral bacteria to challenging micro environments - Answer-early
colonizers are exposed to a pH of 3-4
late in colonization, bacteria are present in an anoxic environment
/.aerotolerant anaerobe - Answer-tolerate oxygen
/.Are transporters integral membrane proteins - Answer-yes. They can either be
importers or exporters. Some are reversibile
/.Assembly of progeny virions - Answer-After the synthesis of viral genome and
proteins, progeny virions are ready to be assembled
Occurs in the cytoplasm or nucleus of host cell
Involves viral proteins as well as host proteins
/.Attachment of Virion to host cell - Answer-This requires interaction between specific
molecules present on the surface of the virion and the host cell (receptors)
The molecules on the virion are viral proteins and are known as receptor binding
proteins they are present on the capsid of non enveloped viruses and envelope of
enveloped viruses
/.Bacillus Anthrasis - Answer-causes anthrax, gram positive rod
/.Bacteria (in terms of energy metabolism) - Answer-they are flexible
diverse organic and inorganic electron donors
oxygen and anaerobic electron acceptors (therefore facultative anaerobes)
fermentation as terminal , sustained mode of energy generation
/.batch pasteurization - Answer-at 63 degrees for 30 minutes will kill some cells but not
endospores
,/.Binal Symmetry - Answer-Some viral capsids have both icosahedral and helical
symmetry
For example the T4 bacteriophage capsid has two parts (head and tail)
The head has the icosahedral symmetry and tail is helical
/.Boiling Water - Answer-at 100 degrees for 15 mins, will kill cells but not endospores
/.Botulism - Answer-caused by clostridium botulinum
it produces a potent neurotoxin (which is inactivated by heating greater over 85)
the mortality rate is high 25%. Death is usually because of respiratory failure
treatment involves mechanical ventilation and therapy with an antitoxin
/.Bovine Rumen - Answer-organ that harbours bacteria that digest cellulose and other
polysaccharides
bacteria allow cow to obtain nutrients from grass/grain diets. Cow provides habitat for
bacterial growth and a continual food supply
/.Campylobacter spp - Answer-Contaminates 90% of chicken and turkey carcasses
Causes high fever (40%) and bloody diarrheae
treatment is with fluid and electrolyte replacement
infections are associated with a ~100 fold increased incidence of Guillian Barre
Syndrome
/.Capnophiles - Answer-Microbes that require high CO2 conditions
/.Cell Numbers increase .......... - Answer-exponentially
/.Cholera - Answer-- Large infections dose depending on whether bacteria are ingested
with food
- causes watery diarrhea. Can cause dehydration if not treated
- treated wit oral or IV and electrolyte supplement
- antibiotic can speed recovery bu is ineffective without fluid replacement therapy
/.Circularization - Answer-through ligatino of cohesive or blunt ends
, a nick is created by a helicase
free 3' end acts as a primer
RNA primer-independant replication of one strand
BUT RNA primer dependant replication of dispaced strand
/.Clostridium gotulinum - Answer-deadly food poisoning
/.Clostridium perfringens - Answer-gas gangrene
/.Clostridium tetani - Answer-tetanus
/.Colonization of Teeth - Answer-adhesion of early colonizers
recruitment of late colonizers
/.Commensals or mutualistic bacteria - Answer-live in the human body, but do not cause
disease
benefit from association with humans
often provide benefits for the human
/.Complex Symmetry - Answer-some viral capsids do not fit either category (helical,
icosahedral, or binal)
for example the poxvirus
/.Covalently Closed Ends - Answer-closed ends are nicked by host helicase
free 3' end forms a hairpin loop and act as 'primer' > viral DNA polymerase starts
synthesis
concatemer is formed, cleaved into individual genomes
Rna primer independant
/.Define anitseptics - Answer-they are chemical agents that kill or inhibit growth of
microorganisms and that are sufficiently non-toxic to be applied to living tissues