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.
Suffolk, Virginia. Suffolk is an independent city in the Commonwealth of Virginia. As of the 2014 census, the estimated population was 86,806 It is the largest city in Virginia by area as well as the 14th largest in the country. Suffolk is located in the Hampton Roads metropolitan area which also includes the independent cities of Chesapeake, Hampton, Newport News, Norfolk, Portsmouth, and Virginia Beach, as well as other smaller cities, counties, and towns of Hampton Roads. With miles of waterfront property on th