Lab Final Exam : pGLO

Question 1

In the pGLO lab, how could you confirm that a transformed cell was expressing the bla gene?

A. It would fluoresce green
B. It would grow on Amp plates
C. If would not grow on ‘LB only’ plates
D. If would only grow on ‘LB only’ plates

Answer 1

B. It would grow on Amp plates

Question 2

After transformation of HB101 by pGLO, why are the cells grown in LB broth for 20 minutes before plating on Amp plates?

A. The Green Fluorescent Protein takes 20 minutes to be transcribed and translated
B. The pGLO plasmid does not fully enter the HB101 cells until 20 minutes after the heat shock
C. The Arabinose promoter needs at least 20 minutes before RNA polymerase can bind to the promoter
D. There is a phenotypic lag of ~20 minutes before the b-lactamase gene for Amp resistance can be expressed
E. The HB101 bacteria are weak after the heat shock treatment, and need 20 minutes to recover

Answer 2

D. There is a phenotypic lag of ~20 minutes before the b-lactamase gene for Amp resistance can be expressed

Question 3

E. coli can absorb the sugar Arabinose from its surroundings. When Arabinose is present,

A. It binds to a repressor protein at the promoter of the Arabinose Operon
B. It changes the conformation of the repressor protein such that RNA polymerase can begin transcribing the Ara operon.
C. It binds to DNA and functions as an enhancer to turn on the Green Fluorescent Protein
D. a and b
E. All of the above

Answer 3

E. All of the above