Week 1 : HW1 Gene Regulation

What does the repressor protein do?

• Allows RNA polymerase to read the gene
• Prevents RNA polymerase from reading the gene
• Reads the gene
• Translates the gene

What is an operon?

• a part of the promoter region of a gene
• a part of RNA polymerase
• a unit made up of linked genes that code for proteins needed to do a specific task
• A protein needed for DNA replication

Tags

NGSS.HS-LS1-1

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

Which type of operon is shown in the image?

• inducible operon
• repressible operon
• positive control operon
• can't determine this from the image

Gene regulation looks a bit different in eukaryotes. Which of the following are unique to Eukaryotes? Select all that apply.

• Transcription factors

• RNA polymerase

• DNA folds over onto itself

• Sections of DNA called enhancers (where transcription factors bind)

The DNA is tightly wrapped around the histone proteins and the gene is methylated.

• The gene is silenced.

• The gene is active.

• It is impossible to tell.

• The gene is on and off at various times.

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

Tags

NGSS.HS-LS1-1

NGSS.HS-LS1-4

Which of the following methods of gene regulation do eukaryotes and prokaryotes have in common?

• Elaborate packing of DNA in chromosomes
• Activator and repressor proteins, which bind to DNA
• The addition of a cap and tail to mRNA after transcription
• The removal of noncoding portions of RNA

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

For a repressible operon to be transcribed, which of the following must be true?

• A corepressor must be present.
• RNA polymerase and the active repressor must be present.
• RNA polymerase must bind to the promoter, and the repressor must be inactive.
• RNA polymerase cannot be present, and the repressor must be inactive.