Gene Expression

Most gene regulation happens at which step along the way?

• translation
• transcription
• signal transduction
• DNA replication

What is the purpose of a promoter on DNA?

• it allows a gene to be transcribed

• it creates a DNA segment

• it is another word for ribosomes

• it is another word for RNA

Which protein binds to the operator and blocks RNA polymerase?

• CAP site

• repressor

• activator

• operator

In the lac operon the genes will be expressed if:

• lactose is absent in the cell

• tryptophan is present in the cell

• lactose is present in the cell

Why are insertion and deletion mutations so harmful?

• They result in a frameshift, which changes the amino acid sequence

• They may result in the same amino acid sequence

• Insertion and deletions are not any more harmful than substitution mutations.

In eukaryotes, proteins that help the RNA polymerase bind to the regulatory region for transcription are called ____.

• transcription factors

• DNa polymerase

• regulatory genes

• operons

What is the name given to part of a DNA molecule that codes for a protein?

• Glucose

• Chromosome

• Gene

• Phosphate

Which of the following statements regarding mRNA processing is correct?

• Exons are spliced together, while introns are cut out

• A poly G tail is added to the end.

• Introns are spliced together, while exons are cut out

• An extra intron is added to the beginning.

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

• The two different cells become mutated

• The proteins expressed in each cell are different

• The two types of cells have a different sequences of DNA

• The genome of the different cells changes when they are assigned their functions

What is the role of an operon in prokaryotic gene expression?

• It regulates of gene activity in response to the needs of the cells

• It makes the nucleotides necessary for DNA replication

• It activates the promoter for gene expression