The DNA double helix is held together by hydrogen bonds and the nucleotide bases Adenine, Guanine, Cytosine, or Thymine. Check out the source I provided. There's a great diagram of the double helix.Source(s): http://www.ba-education.demon.co.uk/for/...eport Abuse. Hydrogen bonds hold the two helices together to form a double helix. I also remember somethign called base stacking, which if i recall was hydrogen bonding of the same strand, which promoted the helical nature and enforced rigidity of the structure.
Norfolk, Nebraska. Norfolk (/ËnÉÉrfÉÉrk/ or /ËnÉÉrfoÊk/) is a city in Madison County, Nebraska, United States, 113 miles northwest of Omaha and 83 miles west of Sioux City at the intersection of U.S. Routes 81 and 275. The population was 24,210 at the 2010 census,[5] making it the ninth-largest city in Nebraska.
2000 Census Population 234,403 1,551,351 2010 Census Population 242,803 1,671,683 Population Change 2000 to 2010 8,400 120,332 Percent Population Change 2000 to 2010 3.6% 7.8% 2013 Population Estimate (Weldon Cooper Center, UVA) 246,392 1,682,842 * Source: 2000 and 2010 Census, and Weldon Cooper Center at UVA * Virginia portion of MSA Norfolk Region TOTAL POPULATION 242,803 100.0% 1,671,683 Population of one race 233,978 96.4% 1,614,302 96.6% 114,304 47.1% 997,082 59.6%