5+Replication+and+Proofreading+Short

Replication

The process of copying DNA to produce two identical DNA molecules.

Replication Fork

The place where DNA strands are unwinding and opening during replication.

Semiconservative Replication

A type of DNA replication where each new double helix contains one original and one new strand.

DNA Helicase

An enzyme that unwinds and separates the DNA strands prior to replication.

Single-Strand Binding Proteins

Proteins that bind to single-stranded DNA to prevent self-pairing or re-annealing.

DNA Primase

An enzyme that synthesizes a short RNA primer to initiate DNA replication.

Leading Strand

The strand of DNA that is synthesized continuously in the 5' to 3' direction.

Lagging Strand

The strand of DNA that is synthesized in short segments called Okazaki fragments.

Okazaki Fragments

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

DNA Ligase

An enzyme that connects Okazaki fragments by forming a covalent bond between the sugar-phosphate backbone.

Mutation Rate

The frequency at which mutations occur in a given length of DNA over a specific period.

Proofreading Mechanisms

Processes that identify and correct replication errors to maintain genetic fidelity.

Exonucleolytic Proofreading

A proofreading mechanism where DNA polymerase removes incorrectly paired nucleotides from the end of the growing DNA strand.

Tautomeric Forms

Rare forms of nucleotides that can lead to mismatches during DNA synthesis.

Topoisomerase

An enzyme that relieves the strain caused by the twisting of DNA during replication.

Chromatin Assembly Factors (CAF’s)

Proteins that assist in the assembly of histones and chromatin following DNA replication.

Telomeres

Repeated sequences at the ends of chromosomes that protect them from degradation.

Telomerase

An enzyme that adds nucleotide sequences to the ends of chromosomes to prevent them from shortening during replication.