Exam 3 Review

Which of the following is properly matched with its function

• Topoisomerase - breaks the H-bonds between strands

• 1. DNA Ligase - removes and replaces RNA primer

• 1. SSBPs - stabilize the open strands of DNA

• 1. DNA Polymerase I - seals the gap between the DNA fragments

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

• regulator
• repressor
• activator
• corepressor

In a dihybrid cross between two heterozygous pea plants (RrYy), where R represents round seeds (dominant) and r represents wrinkled seeds (recessive), while Y represents yellow seeds (dominant) and y represents green seeds (recessive), what fraction of the offspring would be expected to have round, yellow seeds?

• 1/16

• 3/16

• 9/16

• 1/4

Tags

NGSS.HS-LS3-2

NGSS.HS-LS3-3

genes within the Lac Operon will be expressed if:

• lactose is absent in the cell
• glucose is present in the cell
• lactose is present in the cell

In eukaryotes, proteins that help the RNA polymerase bind to the regulatory region for transcription are called ____________.

• transcription factors
• topoisomerase
• regulatory genes
• activators

Tags

NGSS.HS-LS1-1

What does the lactose do to the Operon? 

• Blocks transcription

• Binds to the repressor, preventing it from binding to the Operator.
  

• The lactose binds the repressor and stops transcription

• Catalyzes transcription

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

The binding of repressors to operators are not reversible.

• True

• False

The lac operon is referred to as a(n) __________ operon.

• inducible

• repressible

• audible

• inaudible

What would the ratio for genotypes be for this Punnett Square?

• 2Bb:2bb
• 2BB:2Bb
• 1BB:2Bb:1bb
• 4Bb

Tags

NGSS.HS-LS3-3