What would make a mixed culture of 2 organisms appear pure on a streak plate? (Y

Question

What would make a mixed culture of 2 organisms appear pure on a streak plate? (You expect to see two colony morphologies but only see one.)

Select one or more:

a. Organisms that are different genetically can have the same colony morphology.

b. The plate was not incubated in favorable temperature conditions for both organisms.

c. The plate was not incubated for very long and the two organisms have different growth rates.

d. You did not flame the loop properly between quadrants but otherwise performed aseptic technique perfectly.

e. You autoclaved the broth prior to making the steak plate. f. A contaminant of different colony morphology got onto the plate.

Explanation / Answer

The correct answer is b and c

Every organism needs optimal growth conditions such as temperature, time period of incubation etc to grow properly. If the plate was not incubated for the required length of time or the temperature of incubation was not set correctly then mixed culture organisms would appear pure on the plate.

Related Questions

Navigate

• Browse (All)
• Browse W
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.