Each strand of the double helix is held together by covalent bonds between deoxyribose sugar and phosphate groups (on the 3' and 5' carbons) (making up the backbone). The bases-purines or pyrimidines - (adenine, guanine, cytosine and thymine) are also bonded onto the deoxyribose sugar (on 1' carbon) covalently.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.
Oakland County, Michigan (MI) County population in 2014: 1,237,868 (95% urban, 5% rural); it was 1,194,156 in 2000. County owner-occupied with a mortgage or a loan houses and condos in 2010: 264,844. County owner-occupied free and clear houses and condos in 2010: 86,144.
A major West Coast port city, Oakland is the largest city in the East Bay region of the San Francisco Bay Area, the third largest city overall in the San Francisco Bay Area, the eighth largest city in California, and the 45th largest city in the United States, with a population of 419,267 as of 2015.