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| | DNA |
 | | If an entire molecule of DNA from the virus "bacteriophage lambda" were shown at this scale, the image would be 970 meters high. |
 | | And for a typical piece of DNA from a eukaryote cell, the image would stretch for 1600 kilometers, about as far as it is from Dallas to Washington, D. Obviously such a large molecule is not fully stretched out inside the cell, but is wound around proteins called histones which protect the DNA. |
 | | This model of DNA appears courtesy of the Image Library of Biological Macromolecules based in Jena, Germany, which maintains a large archive of spectacular computer graphics of DNA, RNA, and proteins. |
| www.ucmp.berkeley.edu /glossary/gloss3/dna.html (354 words) |
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