BIO 181 FINAL EXAM UPDATED ACTUAL
QUESTIONS WITH CORRECT ANSWERS (2026)
●● The lactose operon is likely to be transcribed when:
Answer: The cyclic AMP and lactose levels are both high within the cell.
●● For a repressible operon to be transcribed, which of the following
must occur?
Answer: RNA polymerase must bind to the promoter, and the repressor
must be inactive.
●● Which of the following, when taken up by the cell, binds to the
repressor so that the repressor no longer binds to the operator?
Answer: Inducer
●● What is a promoter?
Answer: Sequence where the RNA polymerase binds and begins
transcription. It is upstream of the sequence encoding the protein
●● Which of the following is a protein produced by a regulatory gene?
Answer: Repressor
, ●● What is a corepressor?
Answer: A small molecule that combines with and activates a repressor
produced by a regular gene
●● What is an operator?
Answer: A regulatory sequence that a repressor can bind to
●● What is a regulatory gene?
Answer: Genes that encode a protein involved in regulation of gene
expression
●● What has to happen for a gene to be transcribed?
Answer: RNA polymerase, which makes new RNA molecules from a
DNA template, must attach to the DNA of the gene.
●● In eukaryotes, general transcription factors:
Answer: Bind to other proteins or to a sequence element within the
promoter called the TATA box.
●● What is a TATA box?
Answer: DNA sequence that indicates where a genetic sequence can be
read and decoded
QUESTIONS WITH CORRECT ANSWERS (2026)
●● The lactose operon is likely to be transcribed when:
Answer: The cyclic AMP and lactose levels are both high within the cell.
●● For a repressible operon to be transcribed, which of the following
must occur?
Answer: RNA polymerase must bind to the promoter, and the repressor
must be inactive.
●● Which of the following, when taken up by the cell, binds to the
repressor so that the repressor no longer binds to the operator?
Answer: Inducer
●● What is a promoter?
Answer: Sequence where the RNA polymerase binds and begins
transcription. It is upstream of the sequence encoding the protein
●● Which of the following is a protein produced by a regulatory gene?
Answer: Repressor
, ●● What is a corepressor?
Answer: A small molecule that combines with and activates a repressor
produced by a regular gene
●● What is an operator?
Answer: A regulatory sequence that a repressor can bind to
●● What is a regulatory gene?
Answer: Genes that encode a protein involved in regulation of gene
expression
●● What has to happen for a gene to be transcribed?
Answer: RNA polymerase, which makes new RNA molecules from a
DNA template, must attach to the DNA of the gene.
●● In eukaryotes, general transcription factors:
Answer: Bind to other proteins or to a sequence element within the
promoter called the TATA box.
●● What is a TATA box?
Answer: DNA sequence that indicates where a genetic sequence can be
read and decoded
