double helix

noun

Definition of double helix

: a helix or spiral consisting of two strands in the surface of a cylinder that coil around its axis especially : the structural arrangement of DNA in space that consists of paired polynucleotide strands stabilized by cross-links between purine and pyrimidine bases — compare alpha-helix, watson-crick model

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Other Words from double helix

double-helical \ ˌdə-​bəl-​ˈhe-​li-​kəl How to pronounce double-helical (audio) , -​ˈhē-​ \ adjective

Examples of double helix in a Sentence

Recent Examples on the Web Then, in 1956, three years after their work on DNA’s double helix, Watson and Crick came up with a plausible explanation. Quanta Magazine, "The Illuminating Geometry of Viruses," 19 July 2017 The first one went out in 1974, when the Arecibo radio telescope in Puerto Rico transmitted a broadcast containing information on everything from the position of Earth in our solar system to the double helix structure of DNA. Sigal Samuel, Vox, "If aliens call, what should we do? Scientists want your opinion.," 6 July 2019 In 1953, scientists proposed that DNA is structured as a double helix, with the chemical bases—adenine (A), cytosine (C), guanine (G), and thymine (T)—stacked up in pairs between two intertwining lengths of sugar and phosphate. Ryan Rossotto, National Geographic, "DNA, explained," 12 June 2019 The moon’s stew of organic molecules and water, many scientists believe, could have resulted in reactions to create amino acids and the bases used to build DNA’s double helix. Paul Voosen, Science | AAAS, "NASA will fly a billion-dollar quadcopter to Titan, Saturn’s methane-rich moon," 27 June 2019 Get our daily newsletter CRISPR-Cas genome-editing systems, often just known as CRISPR, are molecular machines that can be programmed to home in on specific sections of DNA in the genome and cut both strands of the double helix molecule. The Economist, "Gene editing is back in the spotlight," 14 June 2019 The increasingly detailed hierarchical picture of the genome that researchers like Dekker, Misteli, Aiden and their colleagues have been building goes something like this: Nucleotides assemble into the famous DNA double helix. Quanta Magazine, "Genetic Geometry Takes Shape," 25 Feb. 2015 The basic unit of DNA is the base pair, one of the rungs on the twisted ladder that makes up the double helix. Cathleen O'grady, Ars Technica, "DNA data from Africans reveals sequences that we’d missed," 24 Nov. 2018 About 99% of the 6 billion steps in the spiral staircase of DNA’s double helix are the same for all of us. Robert Plomin, WSJ, "Our Fortunetelling Genes," 15 Nov. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'double helix.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of double helix

1954, in the meaning defined above

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The first known use of double helix was in 1954

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Cite this Entry

“Double helix.” The Merriam-Webster.com Dictionary, Merriam-Webster Inc., https://www.merriam-webster.com/dictionary/double%20helix. Accessed 9 December 2019.

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More Definitions for double helix

double helix

noun

English Language Learners Definition of double helix

technical : the shape formed by two parallel lines that twist around each other

double helix

noun

Medical Definition of double helix

: a helix or spiral consisting of two strands in the surface of a cylinder that coil around its axis especially : the structural arrangement of DNA in space that consists of paired polynucleotide strands stabilized by cross-links between purine and pyrimidine bases — compare alpha-helix, watson-crick model

Other Words from double helix

double-helical \ -​ˈhel-​i-​kəl How to pronounce double-helical (audio) , -​ˈhē-​li-​ How to pronounce double-helical (audio) \ adjective

More from Merriam-Webster on double helix

Britannica.com: Encyclopedia article about double helix

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