1. Autoclaving isthe best method of sterilization because:
❏ It is bacteriostatic → bactericidal
❏ The pressure makes the organism more sensitive to heat
❏ It kills both the spores and vegetative cells
❏ The high temperature oxidizes bacteria
*Uses moist heatsignificantly affects coagulation of proteins (Ex. Pressure Cooker)
2. Alpha hemolytic streptococci are the most abundant:
❏ Wound contaminating organisms → combination of aerobic and anaerobic
❏ Skin contaminants → Staphylococcus epidermidis, Enterococcus, Viridans strep
❏ Normal throat bacteria → Streptococcus viridans
❏ Normal stool organisms → enterococci, enterobacter, Klebsiella
3. Based on their oxygen requirement, Clostridium is classified as:
❏ Obligate aerobe - Pseudomonas
❏ Microaerophile → Campylobacter
❏ Facultative anaerobe → most pathogenic organisms; Enterobacteriaceae
❏ Anaerobe → GRAM (+), SPORE FORMING
4. The presence of pili increases bacterial virulence by:
❏ Increasing attachment to host cells → sex pili involved in exchange of genetic
material
❏ Preventing phagocytosis → capsule
❏ Blocking surface antibodies→ biofilm
❏ Producing bacterial toxins→ endotoxin and exotoxin present in gram (+) and (-)
organisms
5. Toxic shock syndrome in menstruating women is caused by?
❏ Staphylococcus aureus → TSS; fever, rash, desquamation
❏ Staphylococcus epidermidis
❏ Streptococcus pyogenes
❏ Streptococcus agalactiae
6. A nonhemolytic, catalase positive, coagulase negative, Gram-positive cocci commonly
associated with urinary tract infection is most likely
❏ Staphylococcus epidermidis → novobiocin sensitive
❏ Staphylococcus saprophyticus → Novobiocin resistant
❏ Streptococcus pyogenes → catalase negative; Bacitracin sensitive
❏ Streptococcus agalactiae → catalase negative
Category | Exams and Certifications |
Comments | 0 |
Rating | |
Sales | 0 |