Primary purpose of the streak plate?

Answer 1

A streak plate technique is used to isolate a single species from a mixed species population. You take a small sample of the mixed species on a sterile loop and streak an agar medium into four zones, reflaming the loop between zones. After incubation, single species colonies should be visible within the fourth zone.

Answer 2

A streak plate is used to determine the streak colour of a mineral. You take the mineral and scratch it against the streak plate, and it will create a coloured streak on the plate. The streak is not always the same colour as the mineral itself.

Answer 3

The primary purpose of the Streak Plate is for part of the identification of rocks and minerals. The sample is scratched across the surface and the color of the "streak" is matched to predetermined colors of what the sample may be. There are other tests involved to come to a more positive identification.

Answer 4

The purpose of making a streak plate is to isolate a single colony of bacteria on an auger filled petri dish. You may need to culture this colony for a later experiment. A colony is created after a single bacteria divides many times creating a mass of genetically identical bacteria. So when performing this procedure keep in mind that you want to dilute a small sample to a point where 1 portion of a petri dish has just 1 bacteria. That way after incubation there is not a humongous cluster of multiple colonies on the plate. This streak plate dilution method is achieved using the following steps:

1) Flame sterilize a wire loop.

2) Cool the loop by touching the auger plate.

3) Dip the loop into the sample.

4) Streak this small sample over a fraction of the plate (e.g. 1/4).

5) Flame the loop to kill the remaining bacteria on the loop (remember this is a dilution).

6) Cool the loop.

7) Place the loop in a small portion of the previous streak and streak out another fraction of the plate.

8) Flame the loop to kill the remaining bacteria.

9) Cool the loop.

10) Streak out another portion of the plate just like before.

11) Repeat this general procedure until you feel that you have sufficiently. diluted the original sample. this usually takes 3 to 4 streak cycles.

12) Incubate the plate.

13) Check and see if you have successfully isolated a colony of bacteria that you were looking for.

14) If you did not isolate a colony then make another streak plate and hope that you get it right the second time.

Answer 5

way of separating bacteria to grow as single colonies

Answer 6

The purpose is to take the mixed sample and isolate the bacteria into pure colonies.

Answer 7

the goal is to obtain isolated colonies of pure mixed culture

Answer 8

isolate a single cell by dilution