DNA and DNA Replication

Flashcards covering key terms and concepts related to DNA structure, replication, and related enzymes.

Nucleotide

The monomer of DNA, consisting of a sugar, a phosphate group, and a nitrogenous base.

Condensation Reaction

The reaction in which monomers bond together, releasing water.

Anti-Parallel Strands

The arrangement of the two DNA strands running in opposite directions.

Complementarity

The property that allows the sequence of bases in one strand to determine the sequence in the other strand.

Leading Strand

The DNA strand that is synthesized continuously in the direction of the replication fork.

Lagging Strand

The DNA strand that is synthesized discontinuously, creating Okazaki fragments.

Okazaki Fragments

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

Helicase

The enzyme responsible for unwinding the DNA double helix during replication.

DNA Ligase

The enzyme that joins Okazaki fragments and seals nicks in the DNA backbone.

DNA Polymerase

The enzyme that synthesizes new DNA strands by adding nucleotides to the 3' end.

Single-Strand Binding Proteins

Proteins that coat single-stranded DNA to prevent it from re-forming a double helix.

Primase

The enzyme that synthesizes RNA primers required for DNA replication.

Telomeres

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

Telomerase

An enzyme that maintains telomere length in germline and stem cells, preventing cellular aging.

Methylation

The addition of methyl groups to DNA, affecting gene expression and cellular differentiation.

Dehydration Synthesis

The process of forming covalent bonds between nucleotide monomers by removing water.

Replication Fork

Y-shaped structure formed during DNA replication where the DNA strands are separated.

Origins of Replication

Specific nucleotide sequences at which DNA replication begins.

Transcription

The process by which mRNA is synthesized from a DNA template.

Cell Cycle

The series of events that cells go through as they grow and divide, including synthesis phase for DNA replication.