Unit 6 Gene Regulation and Expression

what does a promoter do?

• it allows a gene to be transcribed
• it creates a DNA segment
• it is another word for ribosomes
• it is another word for RNA

A protein that binds to the operator and blocks the RNA polymerase

• regulator
• repressor
• activator
• corepressor

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

• lactose is absent in the cell
• glucose is present in the cell
• lactose is present in the cell

Why are insertion and deletion mutations so harmful?

• They change all of the codons from the mutation on down the line, which changes the amino acid sequence
• They insert things that an organism doesn't need.
• They often delete things that organisms need.
• Insertion and deletions are not any more harmful than substitution mutations.

Identify the SUBSTITUTION mutation from the following DNA sequence: 
ATG CCA AAT

• ATG TCA AAT
• ATG CCT AAA T
• ATC CA  AT
• ATG CCA AAT

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

• transcription factors
• topoisomerase
• regulatory genes
• activators

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 is correct?

• Exons are included in the protein sequence, while introns are left out
• Introns are included in the protein sequence, while exons are left out
• Exons and Introns can both be included or left out depending on the protein
• Exons and Introns are both part of the mRNA sequence, but only exons are part of the rRNA and tRNA

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 is the role of operons in prokaryote gene expression?

• It makes the genes prokaryotes be turned on
• It accounts for the regulation of gene activity in response to the needs of the cells
• To make DNA for the gene
• To make the gene turn of and off