Lesson 2: Review Questions

1. On which of the plates would you expect to find bacteria most like the original non-transformed E.coli colonies you initially observed? Explain your predictions.  (Athira)
   
   The negative control plate labeled “LB” because there were no new solutions added except the nutrient broth which allowed the E.coli to grow. It will not glow under UV light since it does not have the gene for fluorescence.
   
   
2. If there are any genetically transformed bacterial cells, on which plate(s) would they most likely be located? Explain your predictions.  (Anisha)
   
   If there are any genetically transformed bacterial cells, they would most likely be located on both of the +pGLO plates, the LB/amp (+) and the LB/amp/ara (+) plates. This is because these plates both contain the antibiotic ampicillin, and only the transformed bacterial cells would be able to survive in a medium containing the ampicillin. These bacterial cells inherited the gene for resistance to ampicillin from the plasmid DNA when the transformation process occurred. In addition, plasmid DNA were only added to the +pGLO microtubule. The genetically transformed cells are most likely not going to be found on the -pGLO plates because these are control plates. In addition, there was no plasmid DNA added to the –pGLO microtubule. Therefore, it would be impossible for transformation to occur on the control plates. 
   
   
   
3. Which plates should be compared to determine if any genetic transformation has occurred? Why?  (Christina)
   
   
   

   The plates that should be compared to determine if any genetic transformation has occurred should be a +pGLO and a –pGLO. By comparing a positive and a negative plate together you will be able to see the difference in them and how different their genetic transformation is. This will prove to you that the positive plate displays a lot more genetic transformation and the negative plate shows little to no genetic transformation.
   
   
4. What is meant by a control plate? What purpose does a control serve?  (Arrjun)
   
   
   A control plate is a guide to interpreting the results of an experiment; typically the control maintains specified strains of bacteria with a known result pattern in any particular test.   These plates are incubated under the same condition as the bacteria being tested. Control plates prove that the results of tests on a bacterium can be trusted and are not the result of a problem with the procedure.  In this experiment both (-) pGLO plates were control plates.  The (-) pGLO plate shows that the E.Coli colony does not grow on Ampicillin (anti-biotic). Without the control, one could not determine that the colonies on the LB/amp (+) pGLO plate were really transgenic cells.