Gene Regulation and Expression

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

• operator

• promoter

• enhancer

• regulatory gene

Regulatory proteins (transcription factors) may

• encourage transcription

• prevent transcription

• stop transcription once its started

• either encourage or prevent transcription

What is 1 in the diagram?

• RNA polymerase

• Inducer

• Repressor

• Operator

What is 2 in the diagram?

• RNA polymerase

• Inducer

• Repressor

• Operator

What does a promoter do?

• binds RNA polymerase for transcription

• binds DNA polymerase for replication

• binds the operator

• binds the repressor

In the lac operon the inducer is

• lactose

• glucose

• galactose

• all of the above

In the top picture the operon is

• on

• off

In order for a gene to be expressed, ___ must bind to the gene's ___, a specific sequence of nucleotides at one end of the gene, thus initiating transcription.

• DNA polymerase, promotor

• DNA polymerase, operator

• RNA polymerase, promotor

• RNA polymerase, operator

Scientists have concluded that gene expression is responsible for the differentiation of the cells of a multicellular organism. Which two observations together most strongly support this conclusion?

• All cells produce the enzymes needed for energy metabolism

• The DNA in each body cell of an organism is essentially identical

• Gene expression can be regulated by a wide variety of mechanisms

• Enzymes needed for digestion are made only be cell lining the digestive tract

Tags

NGSS.HS-LS1-1

NGSS.HS-LS1-4

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