DNA Replication Processes

These flashcards cover the processes and components involved in DNA replication.

What are the two main processes in DNA replication?

Separating the original DNA strand and building the complementary strand.

What is the role of DNA helicase in DNA replication?

DNA helicase unwinds the double helix by breaking hydrogen bonds between complementary base pairs.

What is the purpose of single-stranded binding proteins (SSBs)?

SSBs prevent the separated DNA strands from rejoining or recoiling.

What does DNA gyrase do during replication?

DNA gyrase relieves tension in the DNA strand to prevent it from recoiling.

Define the replication fork in DNA replication.

The area where the double helix unwinds and separates during the replication process.

What is the function of DNA polymerase III?

DNA polymerase III synthesizes the new DNA strand in the 5' to 3' direction using the original strand as a template.

Why is RNA primer necessary in DNA replication?

RNA primer provides a free 3' end for DNA polymerase to start adding nucleotides.

What are Okazaki fragments?

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

What is the leading strand in DNA replication?

The strand that is built continuously in the same direction as the replication fork opens.

How is the lagging strand synthesized?

The lagging strand is synthesized discontinuously in short segments called Okazaki fragments.

What role does DNA polymerase I play in DNA replication?

DNA polymerase I removes RNA primers and replaces them with DNA nucleotides.

What is the function of DNA ligase?

DNA ligase joins Okazaki fragments on the lagging strand by forming phosphodiester bonds.

What important rule must be remembered about DNA synthesis direction?

DNA is always synthesized in the 5' to 3' direction.

What happens to the RNA primers during DNA replication?

RNA primers are removed and replaced with DNA by DNA polymerase I.

What is meant by the antiparallel nature of DNA strands?

One DNA strand runs in the 5' to 3' direction while the complementary strand runs in the 3' to 5' direction.