DNA Replication Review

A set of vocabulary flashcards based on key concepts from DNA replication.

S phase

The phase during which a cell replicates its DNA to make copies of its chromosomes.

Replication forks

Y-shaped junctions formed when DNA opens at the replication origin.

Origin recognition complex (ORC)

A complex that recognizes the replication origin to initiate DNA replication.

Eukaryotic genome

Has thousands of replication origins where DNA replication begins.

Antiparallel

Refers to the two newly synthesized DNA strands that are of opposite polarities.

5′-to-3′ direction

The direction in which a new DNA strand is synthesized.

Primase

An RNA polymerase that synthesizes RNA primers for DNA replication.

Okazaki fragments

Short sequences of DNA synthesized on the lagging strand during replication.

Sliding DNA clamp

A protein that increases the efficiency of DNA polymerization by keeping DNA polymerase stably bound to the DNA.

DNA ligase

Enzyme that joins Okazaki fragments by catalyzing the formation of phosphodiester bonds.

End replication problem

The inability of the replication machinery to replace the last primer of the lagging strand with DNA.

Telomerase

An enzyme that resolves the end replication problem in eukaryotes by extending the 3' end of the parental DNA strand.

Complementary base-pairing

The process by which nucleotides pair with their complementary bases during DNA replication.

DNA polymerases

Enzymes that synthesize DNA by adding nucleotides to a growing DNA strand; prokaryotes have five types: I, II, III, IV, and V.