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The following gel shows the results of a crime scene investigation.  Lane 1 shows a DNA sample that was obtained from the scene of a crime (there was evidence of the criminal cutting himself, so it’s the criminal’s blood sample that produced the DNA bands in lane 1). Lanes 2-7 shows a DNA sample from six potential suspects held in connection with the crime.  Which suspect (#2 through #7) is most likely to have committed the crime?

In the following picture, the bands are orange in color because of ————— binding to ————–.

After transformation of E. coli with pGFP , cells that take up the plasmid exhibit fluorescence upon exposure to UV because of expression of ————protein from the plasmid DNA.  

While performing a quadrant streak (also called the streak plate method) with a bacterial sample, the purpose of sterilizing the loop between each quadrant is:

The presence of more than one kind of colony on an agar plate indicates that the original sample used to streak the plate consists of a mix of different types of bacteria.

The following picture taken from a rotting potato? What conclusions can you make from the clear zones seen on the plate?

If you begin with 10 bacteria and the bacteria divide exponentially, how many bacteria will you have at the end of 2 hours?  The generation time of the bacteria is 20 minutes.

You are determining the purity of water sample by plating a small volume on a media that selectively allows the growth of coliforms.  A colony that would grow on this media would appear ——— color upon gram staining.

A patient went to the ER with severe wound infection of the leg after swimming in a lake.  Gram staining of a sample from his wound showed the following results.  Based on this picture, the bacteria isolated from the wound can be described as which of the following?

  —————- cells have a thin layer of peptidoglycan, while ————— cells have a thick layer of peptidoglycan in their cell walls.