Lesson 5 Gene Expression

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

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

If an mRNA molecule has introns and exons in it, where is it?

• At a ribosome
• In the nucleus
• In a prokaryotic cell
• could be in the nucleus or the ribosome

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

• promoter
• repressor
• operator
• gene

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

What part of a eukaryotic gene often has a TATA box?

• primer

• promoter

• signal peptide

• terminator

What is the non-coding portion of the mRNA transcript that is removed during processing?

• intron

• exon

• 5'cap

• poly-A tail

What does the lactose do to the Operon? 

• Blocks transcription because of the energy it provides
• Allows the repressor to be unbind from the Operator.
  
• The lactose binds the lactose and stops transcription
• Allows for the transcription to speed

Which of the following statements regarding mRNA is correct?

• Exons are included in the protein sequence, while introns are left out
• Introns are included in the protein sequence, while exons are left out
• Exons and Introns can both be included or left out depending on the protein
• Exons and Introns are both part of the mRNA sequence, but only exons are part of the rRNA and tRNA

Tags

NGSS.HS-LS1-1

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