Gene Expression

If glucose is high and lactose is high, will the lac operon be on or off?

• On

• Off

What is the role of single-stranded binding proteins?

• To unwind the DNA

• To prevent re-annealing of the DNA strands

• To relieve tension in the DNA

• To help RNA leave the nucleus

Which is NOT a form of regulation of gene expression?

• Protein degradation

• Transcriptional regulation

• DNA degradation

• Translational regulation

Which of the following are proteins?

• Operator

• Repressor

• Activator

• Promoter

In the tryptophan operon, when tryptophan is high, the operator will be ___ because tryptophan is ____

• on; bound to the activator

• on; bound to the repressor

• off; bound to the activator

• on; bound to the repressor

What is the function of topoisomerases?

• To unwind the two DNA strands

• To relieve the tension created by DNA unwinding

• To prevent DNA strands re-annealing

• To extend the telomeres

Where does the ribosome first bind in prokaryotes?

• 5' cap

• Poly-A tail

• Promoter

• Shine-Dalgarno sequence

What are the three stop codons?

• AUG, UGC, UUU

• UUC, UUG, UUA

• UAA, UAG, UGA

• CCC, UUU, AAA

What is the "best" form of regulation of gene expression, in terms of energy use?

• Protein degradation

• Transcriptional control

• Translational control

• Regulation type doesn't matter

In order to create iPS cells, scientists modify somatic cells by injecting:

• New DNA

• Specific transcription factors

• Micro RNA

• Specific polymerases