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Double helix

Definition(s)

The twisted-ladder shape that two linear strands of DNA assume when complementary nucleotides on opposing strands bond together.

Definition from: Human Genome Project InformationThis link leads to a site outside Genetics Home Reference. at the U.S. Department of Energy

Double helix is the description of the structure of a DNA molecule. A DNA molecule consists of two strands that wind around each other like a twisted ladder. Each strand has a backbone made of alternating groups of sugar (deoxyribose) and phosphate groups. Attached to each sugar is one of four bases: adenine (A), cytosine (C), guanine (G), or thymine (T). The two strands are held together by bonds between the bases, adenine forming a base pair with thymine, and cytosine forming a base pair with guanine.

Definition from: Talking Glossary of Genetic TermsThis link leads to a site outside Genetics Home Reference. from the National Human Genome Research Institute

Related discussion in the Handbook

See also Understanding Medical Terminology.

 
Published: August 25, 2014