The phosphate of one deoxyribonucleotide binding to the 3' carbon of the deoxyribose of another forms the sugar-phosphate backbone of the DNA (the sides of the "ladder"). The hydrogen bonds between the complementary nucleotide bases (adenine-thymine; guanine-cytosine) form the rungs. Note the antiparallel nature of the DNA. One strand ends in a 5' phosphate and the other ends in a 3' hydroxyl.
Illustration of The Chemical Structure of
DNA.jpg by Gary E. Kaiser, Ph.D.
Professor of Microbiology, The Community College of Baltimore County, Catonsville Campus
This work is licensed under a Creative Commons Attribution 4.0 International License.
Based on a work at http://faculty.ccbcmd.edu/~gkaiser/index.html.
Last updated: August, 2018
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