September 23, 2021: Pharmaceutical Interview Questions and Answers

#PureCulture # MostCommonMethodToIsolateIndividualCells #StreakPlateMethod

1. What is pure culture?

A pure culture is a population of cells or multicellular organisms growing in the absence of other species or types in which cells are genetic clones of one another.

2. What is most common method to isolate individual cells and produce a pure culture?

The most common method to isolate individual cells and produce a pure culture is to prepare a streak plate method.

3. Explain Streak Plate Method.

a. Sterilize the inoculating loop by heating it until red hot in a flame until it is red hot. Allow it to cool.

b. Pick up a loop full of liquid inoculum or bacterial growth from the surface of an agar plate and, starting about 2.5 cm in from the edge of the plate, streak lightly back and forth with the loop flat, making close, parallel streaks back to the edge of the plate to a quarter of the plate.

c. Sterilize the loop and cool again, going back to the edge of area first quarter that you just streaked, extend the streaks into the second quarter of the plate.

d. Repeat the same process for remaining two quarter of the plate.

e. Flame and cool the loop again.