Lecture 15
15 Questions
0 Views

Choose a study mode

Play Quiz
Study Flashcards
Spaced Repetition
Chat to Lesson

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What is the major mechanism for controlling the production of a protein encoded by a given gene?

  • Ribosomal regulation
  • Post-translational modification
  • Transcriptional control (correct)
  • DNA replication control

In unicellular organisms, genes are regulated to adjust to changes in which environments?

  • Microbial and ecological
  • Biological and physiological
  • Chemical and genetic
  • Nutritional and physical (correct)

Roughly half of the genes in E. coli are organized into what structures?

  • Chromosomes
  • Ribosomes
  • Plasmids
  • Operons (correct)

What must E. coli RNA pol associate with in order to initiate transcription?

<p>σ70 (B)</p> Signup and view all the answers

What binds to the promoter of the lac operon?

<p>σ70 (D)</p> Signup and view all the answers

What blocks the start site of transcription in the absence of lactose?

<p>Lac repressor (D)</p> Signup and view all the answers

What happens to transcription of the lac operon in the absence of lactose?

<p>It is repressed (D)</p> Signup and view all the answers

What releases the lac repressor from the operator sequence, de-repressing transcription?

<p>Lactose (C)</p> Signup and view all the answers

What is a better energy source than lactose for E. coli?

<p>Glucose (C)</p> Signup and view all the answers

What does E. coli synthesize in response to low glucose levels?

<p>cAMP (A)</p> Signup and view all the answers

What protein does cAMP bind to and activate?

<p>CAP (A)</p> Signup and view all the answers

What greatly stimulates the rate of transcription initiation by interacting with RNA pol?

<p>CAP (A)</p> Signup and view all the answers

In the presence of high tryptophan levels, what happens to the trp operon?

<p>It is repressed (A)</p> Signup and view all the answers

What are the major processes that regulate protein concentrations in eukaryotes?

<p>Transcription, mRNA degradation, mRNA translation, and protein degradation (D)</p> Signup and view all the answers

What controls cell protein concentration by gene transcription, mRNA degradation, protein translation, and protein degradation?

<p>Cell protein concentration (A)</p> Signup and view all the answers

Study Notes

Transcriptional Control in Prokaryotes and Eukaryotes

  • E. coli RNA pol must associate with a sigma factor, commonly σ70
  • σ70 binds to the promoter of the lac operon
  • Lac repressor binds to the operator, blocking the start site when lactose is absent
  • Transcription of the lac operon is repressed in the absence of lactose
  • When lactose is present, it binds to the lac repressor, releasing it from the operator sequence and de-repressing transcription
  • Glucose is a better energy source than lactose
  • E. coli synthesizes cAMP in response to low glucose levels
  • cAMP binds to and activates a transcriptional activator protein called CAP
  • CAP interacts with RNA pol and greatly stimulates the rate of transcription initiation
  • The trp operon is repressed in the presence of high tryptophan levels
  • Cell protein concentration is controlled by gene transcription, mRNA degradation, protein translation, and protein degradation
  • Major processes that regulate protein concentrations in eukaryotes include transcription, mRNA degradation, mRNA translation, and protein degradation

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Quiz Team

Description

Test your knowledge of transcriptional control in prokaryotes and eukaryotes with this quiz. Explore key concepts such as RNA polymerase association, promoter binding, lac operon regulation, cAMP signaling, and protein concentration regulation.

More Like This

Lecture 15 Quiz
14 questions

Lecture 15 Quiz

WellKnownElation avatar
WellKnownElation
lecture 15
36 questions

lecture 15

HopefulCalcium avatar
HopefulCalcium
Lecture 15: Big Data Techniques
37 questions
Use Quizgecko on...
Browser
Browser