true and false #4

Réussis tes devoirs et examens dès maintenant avec Quizwiz!

A chaperone protein is used to aid in the transport of other proteins across cellular membranes.

False

A distinguishing feature of control of gene expression in prokaryotes is that transcription and translation occur completely independently of each other.

False

Enhancers are regulatory sites that are next to the promoter.

False

In a repressible operon, the repressor alone can bind to the operator and shut down transcription.

False

In the operon model of gene regulation, transcription is shut off by the binding of the repressor to the promoter.

False

Many of the DNA sequences to which negative or positive regulatory proteins bind have the same sequence on both strands of DNA reading in the 5'-3' direction.

False

Negative regulation of gene expression usually takes place through enhancement of RNA polymerase activity.

False

One function of chromatin is to increase transcription to a high basal level.

False

RNA polymerase III transcribes all protein-encoding genes.

False

The mechanisms of gene regulation discovered in E. coli are not found in most other prokaryotes.

False

There is only one site on the operator to which the lac repressor binds.

False

A locus control region acts in cis at a long distance.

True

An underlying principle of prokaryotic gene regulation is that it occurs through the binding of regulatory proteins to specific DNA sequences.

True

Attenuation of gene expression is unique to prokaryotes, because it requires translation of a leader sequence at the same time transcription is taking place.

True

Attenuation of the trp operon requires the presence of tryptophanyl-tRNAtrp.

True

Bacteriophage T7 promotors are recognized by both E. coli RNA polymerase as well as T7- specific RNA polymerase.

True

Basal transcription factors bind to the promoters of all protein-encoding genes.

True

Because there is no nuclear membrane in prokaryotes, transcription and translation from a single gene can be taking place at the same.

True

Both inducers and corepressors lead to allostearic alterations in the repressor molecule.

True

Genomic imprinting is an example of epigenetic alteration of DNA.

True

In prokaryotes, the primary point of gene regulation occurs by either blocking or enhancing transcription.

True

In repressor quenching, a repressor protein binds directly to an activator protein.

True

In the trp operon, the protein repressor alone cannot bind to the operator to be a negative regulator.

True

Positive regulators actually physically bind to RNA polymerase and enhance the enzyme's ability to initiate transcription.

True

The concept that proteins bind to DNA and regulate transcription holds true for both positive as well as negative regulation of gene expression.

True

The max gene is expressed at all times.

True

The occurrence of constitutive mutations of all three of the lactose utilizing enzymes indicates that their synthesis is regulated together, probably by another gene.

True

The presence of a diffusable gene product (protein) is a requirement for genes to act in trans.

True

Trans-acting elements are genes located somewhere other than at the target gene and encode proteins that regulate another gene.

True

cis-acting elements are DNA sequences that serve as attachment sites for DNA-binding proteins that regulate the initiation of transcription.

True


Ensembles d'études connexes

World History Exam 1a ch. 1-3, pages 3-86

View Set

Ch 10 Concepts of Emergency and Disaster Preparedness

View Set

ap psych - U5 practice questions

View Set

Articles of Confederation, Constitutional Convention, and Ratification (oh my!)

View Set

Chapter 11 Exceptions and Advanced File I/O

View Set