DNA Structure and Replication

These flashcards cover key concepts related to DNA structure and replication, including enzymes, processes, and the differences between eukaryotic and prokaryotic DNA replication.

Chargaff's rule

States that in DNA, the amount of adenine equals thymine and the amount of cytosine equals guanine.

PCR

Polymerase Chain Reaction, a method to amplify DNA sequences.

Helicase

An enzyme that unwinds the DNA double helix during replication.

Okazaki fragments

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

DNA polymerase III

The main enzyme that adds nucleotides to the growing DNA strand during replication.

Sliding clamp

A protein that holds DNA polymerase in place on the DNA strand during replication.

Telomerase

An enzyme that extends telomeres to prevent chromosome shortening during replication.

Primase

An enzyme that synthesizes short RNA primers to initiate DNA replication.

5' and 3' ends

Refers to the directionality of DNA strands; DNA synthesis occurs in the 5' to 3' direction.

Replication fork

The area where the double helix separates to allow for replication.

Proofreading

The process by which DNA polymerase checks and corrects erroneous nucleotides.

Ligase

An enzyme that connects Okazaki fragments by forming phosphodiester bonds.

Processive enzyme

An enzyme that can catalyze successive reactions without releasing its substrate.

Single-stranded binding proteins

Proteins that stabilize single-stranded DNA during replication.

Eukaryotic vs. Prokaryotic replication

Eukaryotes have multiple origins of replication, while prokaryotes have one.

End replication problem

The issue where the lagging strand cannot be fully replicated, leading to chromosome shortening.