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.
Norfolk's county town and only city is Norwich, one of the largest settlements in England during the Norman era. Norwich is home to Norfolk's only university, the University of East Anglia, and is the county's main business and culture centre.his is reflected in Norfolk's economy which is dominated by agriculture and tourism. One of England's National Parks, The Broads, lies partly within the county, and historical sites, such as the centre of Norwich, also contribute to tourism.