TLS Online TPP Program

#Question id: 1491


All cancer-causing agents identified thus far have what feature in common?

#Unit 4. Cell Communication and Cell Signaling
  1. They are all found in cigarette smoke.

  2. They are all mutagenic.

  3. They are all chemicals.

  4. They do not have any features in common.

More Questions
TLS Online TPP Program

#Question id: 2634

#Unit 2. Cellular Organization

Tryptophan, the end-product of the enzymes encoded by the trp operon, therefore acts as a co-repressor and inhibits its own synthesis through:

TLS Online TPP Program

#Question id: 2635

#Unit 2. Cellular Organization

In E. coli, deleting the ribosome binding site and region 1 of the trp attenuator and leaving the remainder of the attenuator intact has which of the following effects?

TLS Online TPP Program

#Question id: 2636

#Unit 1. Molecules and their Interaction Relevant to Biology

Which of the following events occur when E. coli is starved for tryptophan?

I.  The ribosome translates leader peptide completely

II. Transcription reads through attenuator into trp EDCBA

III. Tryptophanyl tRNA is not formed

IV. A stem loop structure involving regions 3 and 4 is formed at attenuator site

TLS Online TPP Program

#Question id: 2636

#Unit 2. Cellular Organization

Which of the following events occur when E. coli is starved for tryptophan?

I.  The ribosome translates leader peptide completely

II. Transcription reads through attenuator into trp EDCBA

III. Tryptophanyl tRNA is not formed

IV. A stem loop structure involving regions 3 and 4 is formed at attenuator site

TLS Online TPP Program

#Question id: 2637

#Unit 2. Cellular Organization

Which of these operons is anabolic?

TLS Online TPP Program

#Question id: 2638

#Unit 2. Cellular Organization

Which of these systems give the best mode for turning trp operon off?