15.1-15.2a: Operons and Gene Regulation

Which molecule can we find the promoter and terminator in?

• DNA
• mRNA
• tRNA
• polypeptide chain

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

• promoter
• repressor
• operator
• gene

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

• regulator
• repressor
• activator
• corepressor

What is the name of the binding site of RNA polymerase in eukaryotes?

• operator
• operon
• inducer
• promoter

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

Which type of operon is shown in the image?

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

Operons are found in the cells of which of the following types of organisms?

• prokaryotes (bacteria)
• eukaryotes (plant and animals)
• animals only
• viruses

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

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

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