DNA Replication 2026

Purpose of DNA Replication

To produce an identical copy of a cell before cell division - needed for growth or repair

Leading Strand

Strand of pre-existing DNA oriented in the 3’ to 5’ direction with respect to direction of replication on which replication is continuous

Lagging Strand

Strand of pre-existing DNA oriented in the 5’ to 3’ direction with respect to direction of replication on which synthesis is discontinuous/fragmented

Okazaki Fragments

Short stretches of newly synthesised DNA found on the lagging strand

Origin of Replication

Site of initiation of DNA replication - Internal stretch in a DNA helix that opens so that each strand is separate for DNA replication

Template Strand

Refers to pre-existing single strand of DNA that has copied into a new strand vis complementary base pairing

Replication fork

The junction nucleotide substrates are being added to a growing DNA chain. Shape resembles ‘Y’

Semi conservation

After replication of one DNA helix each of the daughter helices that result contain one newly-synthesised and one pre-existing strand of DNA

Base Pair Rule

A-T | C-G

Nucleotide

Base building blocks of nucleic acids DNA and RNA. An organic compound made up of a nitrogenous base, a sugar and a phosphate group