• synonyms

junk DNA

  1. segments of DNA that have no apparent genetic function.
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Origin of junk DNA

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

British Dictionary definitions for junk dna

junk DNA

  1. DNA that consists of repeated sequences of nucleotide and has no apparent function
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Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

junk dna in Science

junk DNA

  1. DNA that serves no known biological purpose, such as coding for proteins or their regulation. Junk DNA makes up the vast majority of the DNA in the cells of most plants and animals, composing, for example, about 95 percent of the human genome.
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The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

junk dna in Culture

“junk” DNA

Segments of DNA along a chromosome that are not genes, do not code for anything that we know of, and whose purpose we do not understand. Approximately ninety-five percent of the human genome falls into this category. The term junk may be misleading, however, as this DNA may have other functions, such as regulating genes during development.

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Some scientists speculate that junk DNA may be archaic material left over from an earlier stage of evolutionary development.
The New Dictionary of Cultural Literacy, Third Edition Copyright © 2005 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.