AP Biology Unit 6

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.

Tags

NGSS.HS-LS1-3

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

Transcription of the structural genes in an inducible operon

• occurs continuously in the cell.

• starts when the pathwayʹs substrate is present.

Muscle cells and nerve cells in one species of animal owe their differences in structure to

• having different genes.

• having different genes expressed.

Tags

NGSS.HS-LS3-2

If you were to observe the activity of methylated DNA, you would expect it to

• be unwinding in preparation for protein synthesis.

• have turned off or slowed down the process of transcription.

Which enzyme was used to produce the molecule in the Figure?

• ligase

• a restriction enzyme

Which of the following separates molecules by movement due to size and electrical charge?

• gel electrophoresis

• gene cloning

Restriction fragments of DNA are typically separated from one another by which process?

• gel electrophoresis

• PCR

Which of the following are characteristics of plasmids? ( more than 1 answer applies)

• Circular DNA strand

• RNA strands

• Contain resistance genes

• Found in eukaryotes

• Found in prokaryotes