TLS Online TPP Program

#Question id: 15656


You are studying a new strain of E. coli that can utilize the disaccharide melibiose very efficiently. You find that utilization depends on the enzyme melibiase, which is encoded by the gene Mel1. Mel1 is not expressed unless melibiose is present in the growth medium. Explain the two regulatory pathways for Mel1 that can explain the behavior of the MelA– and MelB– mutations. For each regulatory pathways what is a role for the inducer melibiose?

#SCPH01 Biochemistry
  1. melibiose and MelB both have a net negative effect on Mel1 activity, and MelA has a net positive effect on Mel1 activity.
  2. melibiose and MelB both have a net positive effect on Mel1 activity, and MelA has a net negative effect on Mel1 activity.
  3. melibiose and MelB both have a net positive effect on Mel1 activity, and MelA also has a net positive effect on Mel1 activity.
  4. melibiose and MelB both have a net negative effect on Mel1 activity, and MelA also has a net negative effect on Mel1 activity.
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TLS Online TPP Program

#Question id: 2946

#SCPH05 I Biotechnology

Which of the following occurs during anaphase A?

TLS Online TPP Program

#Question id: 2946

#SCPH28 | Zoology

Which of the following occurs during anaphase A?

TLS Online TPP Program

#Question id: 2947

#SCPH01 Biochemistry

You perform an experiment where you prevent Cdc20 from binding to APC  in a cell line that usually completes the cell cycle in 60 minutes. Your experiment prevents Cdc20 from binding to APC for 120 minutes, and then you fix and stain the DNA, securin, separase and cohesin proteins. Which of the following would NOT be found in the observed cell?

TLS Online TPP Program

#Question id: 2947

#I Life Science/ Life Sciences Group – I-V

You perform an experiment where you prevent Cdc20 from binding to APC  in a cell line that usually completes the cell cycle in 60 minutes. Your experiment prevents Cdc20 from binding to APC for 120 minutes, and then you fix and stain the DNA, securin, separase and cohesin proteins. Which of the following would NOT be found in the observed cell?

TLS Online TPP Program

#Question id: 2947

#SCPH05 I Biotechnology

You perform an experiment where you prevent Cdc20 from binding to APC  in a cell line that usually completes the cell cycle in 60 minutes. Your experiment prevents Cdc20 from binding to APC for 120 minutes, and then you fix and stain the DNA, securin, separase and cohesin proteins. Which of the following would NOT be found in the observed cell?

TLS Online TPP Program

#Question id: 2947

#SCPH28 | Zoology

You perform an experiment where you prevent Cdc20 from binding to APC  in a cell line that usually completes the cell cycle in 60 minutes. Your experiment prevents Cdc20 from binding to APC for 120 minutes, and then you fix and stain the DNA, securin, separase and cohesin proteins. Which of the following would NOT be found in the observed cell?