labo Flashcards
1
Q
what contains endo agar
A
- contains FUSCHSIN SULFITE (indicator that turns red in acid conditions) and LACTOSE which coliforms ferment to produce lactic acid
- non-lactose fermenter= colorless
2
Q
why incubation temperature of mFc is higher
A
to inhibit growth of pathogens that are not from fecal origin
3
Q
composition of RCAF + inhibits what
A
- FUROXONE selection and anaerobic medium inhibits growth of STAPHYLOCOCCI or MICROCOCCI
- Pink colonies = P. avidum (mucoid) or P. granulosum (dry)
- Buff-colored colonies: P.acnes
4
Q
KEA inhibits what + composition
A
- kanamycin and azide inhibits growth of GRAM - and most of GRAM +
- esculin is split yielding a phenolic compund which binds with the iron present= black color
5
Q
EMB inhibits what
A
- eosin and methylene blue inhibit most microorganisms that are NOT GRAM - ENTERIC BACILLI
6
Q
S4 (single step selection for staphylococci
A
- 5% sodium chloride and potassium tellurite inhibit most GRAM + AND -
- S. aureus reduces tellurite to produce anthralites black colonies
7
Q
nessler’s reagent
A
Nessler’s reagent turns yellow/brown upon reactiong with ammonia
