Chapter 10

DNA Replication

The process of making an identical copy of a DNA molecule.

Semiconservative Replication

DNA replication mechanism where each new DNA molecule consists of one strand from the original DNA molecule and one newly synthesized strand.

Meselson-Stahl Experiment

Experiment confirming semiconservative DNA replication by using isotopes of nitrogen to track DNA replication.

DNA Polymerase

Enzyme responsible for catalyzing the synthesis of new DNA strands by adding nucleotides to the growing DNA chain.

Leading Strand

The DNA strand that is synthesized continuously in the 5’ to 3’ direction during DNA replication.

Lagging Strand

The DNA strand that is synthesized discontinuously in short Okazaki fragments during DNA replication.

Okazaki Fragments

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

DNA Ligase

Enzyme that joins Okazaki fragments by forming covalent bonds between adjacent DNA fragments.

Topoisomerase

Enzyme that removes and introduces supercoils in DNA during replication.

Helicase

Enzyme that promotes the unwinding of DNA at the replication fork.

Primase

Enzyme responsible for synthesizing RNA primers during DNA replication.

DNA Repair

Mechanisms to correct errors in DNA replication to maintain genomic integrity.

Mutation

Permanent change in the nucleotide sequence of the genome, often resulting from errors in DNA replication.

DNA Lesions

Abnormal modifications in DNA structure caused by chemical reactions or environmental damage.