DNA Replication and the Human Genome

A set of vocabulary flashcards covering key concepts related to DNA replication and the human genome.

DNA

Deoxyribonucleic acid, the molecule that contains genetic information.

Nucleotide

The basic building block of DNA, consisting of a deoxyribose sugar, a phosphate group, and a nitrogenous base.

Phosphodiester bond

The bond between the phosphate group of one nucleotide and the sugar of another, linking nucleotides together.

Complementary strands

DNA strands that are opposite in sequence and run in opposite directions; A pairs with T and C pairs with G.

Semiconservative replication

The process of DNA replication where each new double helix consists of one old (parental) strand and one newly synthesized strand.

Okazaki fragments

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

DNA polymerase III

An enzyme responsible for synthesizing new DNA strands by adding nucleotides to the 3' end of a growing DNA chain.

Origins of replication (ORI)

Specific sequences in DNA where replication begins.

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 in short segments away from the replication fork.

DNA helicase

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

Topoisomerase

The enzyme that relieves strain in the DNA ahead of the replication fork by making temporary cuts in the DNA.

DNA ligase

An enzyme that connects Okazaki fragments by forming phosphodiester bonds.

Hydrogen bonds

Weak bonds that hold complementary nitrogen bases together in the DNA double helix.

Template strand

The original DNA strand that serves as a guide for the synthesis of a new strand.

Genome

The complete set of genes or genetic material present in a cell or organism.

Chromosome

A structure made of DNA and proteins that contains genetic information.

Autosomes

Non-sex chromosomes that contain genes for general functions such as growth and metabolism.

Sex chromosomes

Chromosomes that determine the sex of an individual (XX for female, XY for male).