AP Biology Gene Regulation and Viruses and Bacteria

The "on/off" switch for an operon is called the

• promoter

• repressor

• operator

• gene

How can a person's muscle cells have the same exact DNA sequences as their nerve cells even though the look and perform completely different?

• The two different cells become mutated

• The proteins expressed in each cell are different

• They actually have different DNA in the two types of cells.

• The genome of the different cells changes

What does the inducer molecule do in an inducable operon?

• it binds to the repressor protein allowing transcription to occur

• it binds to the promoter allowing transcription to occur

• it binds to the operator and stops transcription

• it binds to the repressor and stops transcription

In the lac operon, the genes within the operon will be expressed if:

• lactose is absent in the cell

• galactose is present in the cell

• lactose is present in the cell

• glucose is absent in the cell

What type of operon is the lac (lactose) operon?

• inducible

• repressible

• positive control

• promoible

Transcription begins at sequences called

• Start Codons

• Promoters

• Origins

• Introns

Which of the following is an example of post-transcriptional control of gene expression?

• the addition of methyl groups to cytosine bases of DNA

• the binding of transcription factors to a promoter

• the removal of introns and splicing together of exons

• gene amplification contributing to cancer

The process by which a cell becomes specialized for a specific structure or function.

• cell multiplication

• cell division

• mitosis

• cell differentiation

A chemical modification of DNA that does not affect the nucleotide sequence of a gene but makes that gene less likely to be expressed.

• methylation

• acetylation

• alternative splicing

• snRPs

What are 2  ways gene expression is controlled in prokaryotes?

• Through inducible and repressible operons

• Through introns and exons

• Through methylation and acetylation

• Through enhancers and distal control elements