AP Biology Unit 5

Which of the following occur during RNA processing? (more than 1 answer applies)

• exons can be removed

• spliceosomes remove introns

• a poly-A tail and GTP cap are added

• DNA helicase unzips DNA

• activator sequences initiate transcription

What kind of chemical bond is found between paired bases of the DNA double helix?

• hydrogen

• ionic

• covalent

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.

What is meant by the description ʺantiparallelʺ regarding the strands that make up DNA?

• The 5ʹ to 3ʹ direction of one strand runs counter to the 5ʹ to 3ʹ direction of the other strand.

• One strand is positively charged and the other is negatively charged.

Which enzyme catalyzes the elongation of a DNA strand in the 5ʹ → 3ʹ direction?

• primase

• DNA ligase

• DNA Polymerase

• helicase

What determines the nucleotide sequence of the newly synthesized strand during DNA replication?

• the nucleotide sequence of the template strand

• the primase used in the reaction

Which of the following separates the DNA strands during replication?

• helicase

• DNA polymerase

• primase

Which of the following covalently connects segments of DNA?

• helicase

• DNA polymerase

• ligase

The leading and the lagging strands differ in that

• the leading strand is synthesized in the same direction as the movement of the replication fork, and the lagging strand is synthesized in the opposite direction.

• the leading strand is synthesized by adding nucleotides to the 3ʹ end of the growing strand, and the lagging strand is synthesized by adding nucleotides to the 5ʹ end.