Exam 12: From Gene to Protein

The lac repressor has been mutated so that its binding site for the operator has been altered to the extent that it is unable to bind to the operator.What is the likely effect of this mutation on the lac operon?

For a firefly to glow,the enzyme luciferase must catalyze a chemical reaction in the cells of the firefly.A scientist uses a chemical to induce a mutation in the luciferase gene in a strain of fireflies.Which of the following is true?

A promoter would be located on

As transcription begins,RNA polymerase binds to a segment of a gene called a(n)

Which of the following is NOT a feature of the genetic code?

Proteins are produced directly from DNA,with no intermediate steps.

The sugar molecule present in RNA is

Most molecules of RNA are ________-stranded.

During translation

The chemical structure of bisphenol A (BPA)resembles

A potential danger of a mutation to an organism is that

Some tRNAs can recognize more than one codon because the base at the third position of their anticodon can pair with any one of two or three different bases in the codon;this phenomenon is called ________.

In humans,the herbicide atrazine helps RNA polymerase bind to the promoter of the gene for the enzyme aromatase.As a result

Which of the following results would most likely occur if introns were not removed from newly made mRNA?

Molecule B in the following image is RNA.

The stop codon is the sequence of bases at which transcription ends.

Which of the following is true of transcription?

The following figure depicts a gene and two different ways that gene could be mutated.How does Mutation A differ from Mutation B?

Which of the following is NOT a mechanism used by cells to reduce gene expression?

Because they are so distantly related,the codons for serine in a black widow spider would probably be much different from the codons for serine in bluebirds.