AP Biology Operons

We know that lactose has a positive impact on the activity of the lac operon. Tryptophan’s presence has a ________________

• Positive feedback

• Negative feedback

• No difference

• Highly positive impact

Tags

NGSS.HS-LS1-3

Which segments of the attenuator together form the repression loop?

• Segment 1-2

• Segment 2-3

• Segment 3-4

• Segment 1-4

Which of these properties do not agree with trp operon attenuator?

• It brings about repression of trp operon

• It consists of one stem loop system

• It has two codons for tryptophan in sequence

• Ribosome stalls at the attenuator

Which of the Ara operon regulation site is actually preventing RNA polymerase from binding and producing the Ara genes BAD?

• O1

• O2

• P

• Z

Which of these Ara genes is a mode of feedback autoregulation?

• Ara A

• Ara B

• Ara C

• Ara D

Tags

NGSS.HS-LS1-3

Which of the Ara promoter regulation is controlled by binding of repressors on the O1 regulating unit?

• P_A

• P_B

• P_C

• P_D

In the absence of glucose, the binding of CRP-cAMP complex to the region near to the lac promoter will

• No significant effect on the transcription of lac genes

• Cause the release of RNA polymerase from the promoter

• Decrease transcription of lac genes

• Increase transcription of lac genes

The lac repressor have which of the following DNA binding motif

• Zinc Finger

• Homodomain

• Leucine zipper

• Helix-turn-helix

Which of the following is a characteristic of the lac operon?

• It is an inducible operon

• It is a repressible operon

• It is always active

• It is not regulated by lactose

In the trp operon, what happens when tryptophan levels are high?

• The operon is activated

• The operon is repressed

• The operon is unaffected

• The operon is induced