Question

You are preparing sterile tubes of LB. If you correctly performed aseptic technique which tube should you expect to see if you incubated the tube at 37°C overnight?

A. clear yellow tube
B. cloudy tube

Answer 1

option a,A correct aseptic technique would likely result in a clear yellow tube after incubation at 37°C overnight due to the absence of bacterial contamination. A cloudy tube would indicate contamination and bacterial growth.

Step-by-step explanation:

When preparing sterile tubes of LB and using aseptic technique, the expected outcome after incubating at 37°C overnight would be a clear yellow tube. If the aseptic technique was correctly performed, no contamination should be present, and hence no bacterial growth should occur, resulting in the medium remaining clear. However, if bacterial growth was present, it would be indicated by a cloudy tube, suggesting that contaminants were introduced during the preparation.

Bacterial growth in broths changes the appearance from clear to cloudy due to the proliferation of bacteria. Therefore, a clear broth after incubation means that sterilization was effective and contamination did not occur during the process. By employing aseptic technique such as the use of sterilized equipment, ensuring a flame-sterilized environment, and minimizing exposure to non-sterile surfaces, the likelihood of producing uncontaminated cultures increases, yielding accurate experimental results.