Ch 18 Gene Regulation

Most gene regulation happens at which step along the way?

• translation
• transcription
• signal transduction
• DNA replication

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

• prokaryotes

• eukaryotes

• animals only

• viruses

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

• operator

• promoter

• enhancer

• regulatory gene

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

• promoter

• enhancer

• operator

• gene

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.

Tags

NGSS.HS-LS3-2

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

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

• transcription factors
• topoisomerase
• regulatory genes
• activators

Tags

NGSS.HS-LS1-1

A small molecule that binds to the repressor and makes it inactive is

• corepressor
• inducer
• promoter
• operator

A small molecule that binds to a repressor and makes it active

• repressor
• regulator
• activator
• corepressor

When a gene transcribes unless turned off by a repressor, it is considered _____ control

• negative
• positive