DNA Replication - Glossary

Antiparallel - Two molecules that are side by side but run in opposite directions. For example: The two strands of DNA are antiparallel, because the "head" of one strand is found where the "tail" of the other strand is.

ATP - AKA, Adenosine triphosphate. It is a nucleotide that is used as a primary energy-transferring molecule in living organisms.

Chromosomes - A threadlike linear strand of DNA and associated proteins in the nucleus of eukaryotic cells. In other words, chromosomes are condensed DNA.

Complementary bases - A base of a nucleotide that pairs only with another specific base. For example: Adenine (A) pairs with Thymine (T), and Guanine (G) pairs with Cytosine (C).

Condensation polymers - All polymers that are formed through a condensation reaction, releasing a by-product molecule such as water (H2O).

DNA - AKA Deoxyribonucleic acid. It is a nucleic acid that contains the hereditary material (genetic instructions) used in the development and functioning of all living organisms. It is found in the nucleus of every cell.

Double-Helix - It is the structure of DNA with the two strands of DNA spiraling about one other, thus creating a long ladder twisted into a helix, or coil.

Enzymes - Biomolecules (mainly proteins) that catalyze (increase rate) of chemical reactions. Used in many reactions in the body such as: Oxygen transfer by Hemoglobin, or unwinding the DNA by Helicase.

Eukaryotic cells - Organisms that have cells with nucleus and other organelles enclosed within a membrane.

Genes - Gene is the basic unit of heredity in a living organism. It is a sequence of nucleotides in the DNA that codes for a specific function.

Genome - A complete set of the chromosomes in an organism. It includes both the genes and the non-coding sequences of the DNA. For example: in humans the genome consists of 46 chromosomes that contain all our genetic information.

Mitosis - the division process in which a eukaryotic cell separates into two daughter cells with identical chromosomes (DNA).

Monomers - A sub-unit or a small molecule that can chemically bond to other monomers to form a polymer.

Nucleic acids - A macromolecule composed of nucleotides; mainly DNA and RNA.

Nucleotides - Molecules that consists of a five-carbon sugar, a nitrogenous base and a phosphate group. It is a sub-unit of nucleic acid.

Phosphodiester bonds - Strong covalent bonds between the phosphorus atom in a phosphate group and two other molecules.

Prokarayotic cells - Cells that lack a membrane-bound nucleus or organelles.

Semi-conservative - A process which produces two copies - each contains one of the original strands and one new strand.

Template - A DNA sequence that is used to build a complementary DNA strand. For example: ATAC (template) = TATG (new strand).