DNA Replication

DNA Replication

The process of making an identical copy of a DNA molecule, ensuring each new cell receives a full set of genetic instructions.

Double Helix

The structure of DNA, consisting of two strands that wind around each other like a twisted ladder.

Helicase

An enzyme that unwinds the DNA double helix by breaking the hydrogen bonds between the base pairs.

Origin of Replication

Specific sites on the DNA molecule where replication begins.

Replication Fork

The Y-shaped structure formed when the DNA double helix is unwound and replication occurs.

Leading Strand

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

Lagging Strand

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

Okazaki Fragments

Short sequences of DNA nucleotides synthesized discontinuously on the lagging strand during replication.

DNA Polymerase

An enzyme that adds complementary nucleotides to the growing DNA strand during replication.

RNA Primer

A short segment of RNA that provides a starting point for DNA synthesis.

DNA Ligase

An enzyme that joins Okazaki fragments together to form a continuous strand.

Topoisomerase

An enzyme that relieves the tension and prevents tangling of the DNA molecule during replication by cutting and rejoining DNA strands.

Antiparallel

Refers to the opposite orientation of the two strands in the DNA double helix; one runs 5' to 3' and the other 3' to 5'.

S Phase

The phase of the cell cycle during which DNA replication occurs.

Proofreading

The function of DNA polymerase that checks and corrects errors during DNA replication.

Semi-conservative Replication

The method of DNA replication in which each new DNA molecule consists of one old strand and one new strand.

Replication Bubble

A region of DNA where the double helix is unwound and replication occurs.

Template Strand

The original DNA strand that serves as a guide for synthesizing a new complementary strand.