Gene Expression and Regulation

What is an operon?

• a part of a ribsome

• a part of a RNA

• a unit made up of linked genes that code for proteins needed to do a specific task

• needed for dna replication

An operon consists of all the the following EXCEPT

• operator
• promoter
• regulatory gene
• genes of the operon

Operons are found in which of the following organisms?

• Bacteria(prokaryotes)

• plants and animals(eukaryotes)

• only animals

• virsuses

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

• promoter
• repressor
• operator
• gene

What does a promoter do?

• binds RNA polymerase for transcription

• binds DNA polymerase for replication

• binds the operator

• binds the repressor

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

• regulator
• repressor
• activator
• corepressor

The lac operon genes only become expressed if:

• lactose binds to repressor

• glucose binds to repressor

• repressor binds to operator

• lactose binds to operator

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

Most gene regulation happens at which step along the way?

• translation
• transcription
• signal transduction
• DNA replication

What is the name of the stretch of DNA where RNA polymerase binds?

• operator

• promoter

• enhancer

• regulatory gene