Gene Expression

How can a person's muscle cells have the same exact DNA sequences as their nerve cells even though they 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

Protein molecules around which DNA is tightly coiled in chromatin

• Histones
• Whey
• Casein
• Hemoglobin

Tags

NGSS.HS-LS1-1

A chemical modification of DNA that does not affect the nucleotide sequence of a gene but makes that gene less likely to be expressed.

• methylation
• acetylation
• transcription
• translation

Tags

NGSS.HS-LS3-2

Which of the following is an example of post-transcriptional control of gene expression?

• the addition of methyl groups to cytosine bases of DNA
• the binding of transcription factors to a promoter
• the removal of introns and splicing together of exons
• gene amplification contributing to cancer

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

• regulator
• repressor
• activator
• corepressor

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

• promoter
• repressor
• operator
• gene

The lac operon genes only become expressed if:

• lactose binds to the repressor
• glucose binds to the repressor
• lactose binds to the operator
• the repressor binds to the operator

Inducible negative control is when when the gene is transcribed by the ____ of a specific molecule

• presence
• absence

Repressible negative control is when when the gene is transcribed by the ____ of a specific molecule

• presence
• absence

What type of operon is the trp (tryptophan) operon?

• inducible
• repressible
• positive control
• promoible