M1 +M2 Flashcards
why is the cell wall important?
- structural barrier
- cell wall includes peptidoglycan
what is a target of penicillin?
- FtsI
is fimbrae/pilus gram- or gram + ?
gram -
under which conditions can pyruvice acid be converted to lactic acid or ethanol?
anaerobic conditions
for prokaryotic growth what is the source for carbon?
protein and sugars
what factors are important in prokaryotic growth?
- food
- temperature
- hydrogen ion conc
- osmotic protection
- oxygen
what are the stages in the bacterial growth?
- lag phase
- exponential phase
- stationary phase
- decline phase
what is the definition of a virus?
- very small, obligate intracellular parasite
what is the development of the oral flora in babies?
- microbiologically sterile until birth
what are the two rules regarding standard infection control?
- all patients maybe a carrier and therefore pose a significant risk
- routine procedures must be sufficiently effective to protect against all possible infections and are routinely applied
what is the golden rule of standard infection control?
the same cross infection control procedures must be used for all patients
what are the structural differences between pro and euk?
pro
- no membrane
- circular chromosme
- peptidoglycan wall
euk
- membrane bound
- linear chromosome
- cell wall or envelope
Give three benefits of culturing bacteria?
- determines viability (aerobic vs anaerobic)
- component special
- provides pure material
give advantages of transport media (general media)?
- includes charcoal which prevents desiccation and absorbs toxic agents
- rich in nutrients
give an advantage of enrichment media?
- addition of blood/serum/extracts will support growth of fastidious organisms
what is the advantage of using blood agar?
supports growth and allows haemolytic profiles to be determined
which media allows the presence of specific substances permits the growth of one organism over another?
- selective media
what does differential media allow you to determine?
incorporation of chemicals produces viable changes in colonies that facilitate identification
classification of cocci
single coccus
pair of cocci
cluster of cocci (staphyloccci)
chains of cocci (streptococci)
classification of rods (bacilli)
- single rod
- chains of rod
- curved rod (vibrio)
- spiral
how can bacteria be biochemically characterised?
metabolic profiling
- Ability to produce acid (urease)
- identification - inoculate single colony
- then compare
how do serological tests determine bacteria?
- Ab specific to microbe
- detect presence of specific IgM Ab to virus/microbe
- rapid detection
what is the effect of agglutination?
antibody clumps with antigen to deactivate/destroy it
why are virulence factors important?
allows us to find out severity of disease
what does MALDI-TOF stand for?
Matrix assisted laser desorption time of flight
what does MALDI-tof do?
- generates a series of ions
- mass analyzer - separates ions by mass to charge ratio
- detection device: detects spectrum of proteins
