AP Bio Unit 6 Review

Bacterial cells that contain pGal will fluoresce blue under ultraviolet light. Which of the following is the most likely outcome of replacing the lacA gene in the E. coli lac operon with the gene encoding pGal?

• When lacY and lac Z are breaking down and transporting lactose, the bacteria will fluoresce blue under ultraviolet light

• lacZ will only produce the enzyme for breaking down galactose in the presence of ultraviolet light

• the repressor enzyme will only be able to bind to the operator under the presence of lactose

• When the regulatory gene is stimulated by lactose, it will cause the gene to fluoresce blue

• All structural genes downstream from the placement of lacA will be inhibited due to this substitution mutation.

Tags

NGSS.HS-LS1-1

Cytosine makes up 38% of the nucleotides in a sample of DNA from an organism.

Approximately what percentage of the nucleotides in this sample will be thymine?

• 12%

• 24%

• 31%

• 38%

In an analysis of the nucleotide composition of DNA, which of the following will be found?

• A = G and C = T

• A + C = G + T

Replication in prokaryotes differs from replication in eukaryotes for which of these reasons?

• Prokaryotic chromosomes have a single origin of replication, whereas eukaryotic chromosomes have many.

• Prokaryotes produce Okazaki fragments during DNA replication, but eukaryotes do not.

Which of the following covalently connects segments of DNA?

• helicase

• DNA polymerase

• ligase

Which of the following synthesizes short segments of RNA?

• helicase

• DNA polymerase

• primase

When DNA is compacted by histones into 10 nm and 30 nm fibers, the DNA is unable to interact with proteins required for gene expression. Therefore, to allow for these proteins to act, the chromatin must constantly alter its structure. Which processes contribute to this dynamic activity?

• methylation and phosphorylation of histone tails

• nucleotide excision and reconstruction

The genetic code is essentially the same for all organisms. From this, one can logically assume all of the following except

• a gene from an organism could theoretically be expressed by any other organism.

• all organisms have a common ancestor.

• DNA was the first genetic material.

• the same codons in different organisms usually translate into the same amino acids.

Tags

NGSS.HS-LS4-1

RNA polymerase moves in which direction along the DNA?

• 3ʹ → 5ʹ along the template strand

• 3ʹ → 5ʹ along the coding (sense) strand

What are the coding segments of a stretch of eukaryotic DNA called?

• introns

• exons