AP Bio Gene Control and Biotechnology

What are the coding segments of a stretch of eukaryotic DNA called?

• introns

• exons

Introns are significant to biological evolution because

• their presence allows exons to be shuffled.

• they protect the mRNA from degeneration.

A mutation in which of the following parts of a gene is likely to be most damaging to a cell?

• intron

• exon

Tags

NGSS.HS-LS3-2

Alternative RNA splicing

• is a mechanism for increasing the rate of transcription.

• can allow the production of proteins of different sizes from a single mRNA

When does translation begin in prokaryotic cells?

• as soon as transcription has begun

• once the pre-mRNA has been converted to mRNA

Why might a point mutation in DNA make a difference in the level of proteinʹs activity?

• It might substitute an amino acid in the active site.

• It might exchange one stop codon for another stop codon.

Tags

NGSS.HS-LS1-1

NGSS.HS-LS3-2

A frameshift mutation could result from

• a base insertion only.

• either an insertion or a deletion of a base.

• a base deletion only.

Tags

NGSS.HS-LS3-2

What does the operon model attempt to explain?

• the coordinated control of gene expression in bacteria

• the mechanism of viral attachment to a host cell

The tryptophan operon is a repressible operon that is

• turned off whenever tryptophan is added to the growth medium

• turned on only when glucose is present in the growth medium.

When this is taken up by the cell, it binds to the repressor so that the repressor no longer binds to the operator:

• inducer

• repressor