DNA Replication Lecture Notes

These flashcards cover key concepts related to DNA replication based on the provided lecture notes.

What is the primary function of DNA polymerase I?

DNA polymerase I is responsible for removing RNA primers and replacing them with DNA nucleotides during DNA replication.

What distinguishes the leading strand from the lagging strand during DNA replication?

The leading strand is synthesized continuously towards the replication fork, while the lagging strand is synthesized in short fragments (Okazaki fragments) away from the fork.

What is the role of helicase in DNA replication?

Helicase unwinds the DNA double helix at the replication forks, separating the two strands.

Define the term 'antiparallel' in the context of DNA strands.

Antiparallel refers to the orientation of the two strands of DNA, where one strand runs 5' to 3' and the other runs 3' to 5'.

What is the role of primase in DNA replication?

Primase synthesizes short RNA primers that provide a starting point for DNA polymerases to begin DNA synthesis.

What are Okazaki fragments?

Okazaki fragments are short segments of DNA synthesized on the lagging strand during replication, which are later joined together by DNA ligase.

Why is topoisomerase important during DNA replication?

Topoisomerase prevents supercoiling of the DNA by making cuts in the DNA helix ahead of the replication fork, allowing it to unwind.

What is the base pairing rule in DNA?

The base pairing rule states that adenine (A) pairs with thymine (T) and cytosine (C) pairs with guanine (G).

What do single-strand binding proteins do during DNA replication?

Single-strand binding proteins bind to the separated DNA strands to stabilize them and prevent them from re-annealing.

Who were the scientists who discovered the structure of DNA and when did they receive the Nobel Prize?

James Watson and Francis Crick, along with Maurice Wilkins, discovered the structure of DNA and received the Nobel Prize in Physiology or Medicine in 1962.