Flashcards in Microbiology Deck (45)
Gram+ organisms stain...
Stain well due to thick peptidoglycan layer
Gram- organisms stain...
Thinner peptidoglycan layer doesn't retain stain well
Endotoxin is produced by...
Part of the cell wall
Exotoxin is produced by...
Exported from the cell
Gram+ cocci in chains are?
Gram+ cocci in clusters are?
The test to classify different Streptococci spp.?
Alpha (partial) - Strep. pneumoniae + viridans
Beta (complete) - Group A (pyogenes) and B Strep.
Gamma (none) - Enterococcus sp.
Examples of: Alpha-haemolytic Streptococci?
Strep. pneumoniae + "viridans" group
Examples of: Beta-haemolytic Streptococci?
Group A Strep. (Strep. pyogenes), Group B Strep.
Examples of: Non-haemolytic Streptococci?
The test to distinguish Staphylococcus aureus from other Staph. spp.?
+ve = Staph. aureus
-ve = other Staph. spp. (common skin commensals)
Treatment of choice for Staph. aureus infection?
Examples of gram- cocci in pairs (diplococci)
Neisseria meningitidis and Neisseria gonorrhoeae
Some examples of Gram- bacilli
Examples of coliforms that are gut commensals
Examples of coliforms that are gut pathogens
E. coli 0157
The name of the toxin produced by E. coli 0157 is...
Treatment of choice for coliform infections?
Examples of strict aerobes (2)
Pseudomonas sp. (Gram- bacilli)
Legionella sp. (Gram- bacilli)
Examples of strict anaerobes (2)
Clostridium spp. (Gram+ bacilli)
Bacteroides spp. (Gram- bacilli)
Treatment of choice for anaerobic infections?
Genetic variation in bacteria is dangerous because...
Resistance to antibiotics may develop.
Gene transfer: Transformation
DNA from dead bacteria is taken up by living bacteria and incorporated into plasmids/bacterial chromosome.
Gene transfer: Conjugation
Sex pilus forms between bacteria to allow transfer of plasmid DNA.
Gene transfer: Transduction
Viruses can transfer bacterial DNA between cells they infect.
The 5 methods of spread of infection are...
Inhalation, Ingestion, Inoculation, mother to Infant, Intercourse
Viruses contain RNA or DNA, never both. True/False?
Size of their capsid (protein coat) limits space
Bactericidal antibiotics inhibit cell growth. True/False?
Kill bacteria directly - bacteriostatic inhibits cell growth
Vancomycin is part of which family of antibiotics?