Sugar-phosphate.
Deoxyribonucleic acid (/diˌɒksiˌraɪbɵ.njuːˌkleɪ.ɨk ˈaesɪd/ ; ˈæSɪD) dna is a molecule that carries most of the genetic instructions used in the, development functioning and reproduction of all known living organisms and many. viruses The backbone of the DNA strand is made from alternating phosphate and sugar residues. The sugar in DNA is 2-deoxyribose, which is a pentose (five-carbon) sugar. The sugars are joined together by phosphate groups that form phosphodiester bonds between the third and fifth carbon atoms of adjacent sugar rings. Nucleotides are arranged in two long strands that form a spiral called a double helix. The structure of the double helix is somewhat like a ladder, with the base pairs forming the ladder’s rungs and the sugar and phosphate molecules forming the vertical sidepieces of the ladder. An important property of DNA is that it can replicate, or make copies of itself. established the structure of DNA. The shape of DNA is a double helix, which is like a twisted ladder. The sides of the ladder are made of alternating sugar and phosphate molecules. The sugar is a pentose called deoxyribose.  The sugar-phosphate backbone is on the outside and the four different bases are on the inside of the DNA molecule. The two strands of the double helix are anti-parallel, which means that they run in opposite directions. The sugar-phosphate backbone is on the outside of the helix, and the bases are on the inside. The backbone can be thought of as the sides of a ladder, whereas the bases in the middle form the rungs of the ladder. Each rung is composed of two base pair The name DNA stands for deoxyribonucleic acid. By breaking down the name, we can understand the structure of the molecule. DNA is a long string of nucleotide units attached to one another. In a single nucleotide there are three components: 1) a sugar molecule, 2) a phosphate group, and 3) a nitrogenous base. (See Figure B-2.) In DNA, the sugar molecule happens to called deoxyribose, hence the name deoxyribonucleic acid. In summary, a double helix of DNA is composed of two spiraling, complementary strands of DNA. Each strand is composed of a sugar and phosphate backbone with varying nitrogenous bases sticking in towards the center. The two strands are joined together at the center by pairing bases lined up with The chemical backbones of the double helix are made up of sugar and phosphate molecules that are connected by chemical bonds, known as sugar-phosphate backbones. The two helical strands are connected through interactions between pairs of nucleotides, also called base pairs. The double helix describes the appearance of double-stranded DNA, which is composed of two linear strands that run opposite to each other, or anti-parallel, and twist together. Each DNA strand within the double helix is a long, linear molecule made of smaller units called nucleotides that form a chain. Exploring a DNA chain The sugars in the backbone The backbone of DNA is based on a repeated pattern of a sugar group and a phosphate group. The full name of DNA, deoxyribonucleic acid, gives you the name of the sugar present-deoxyribose. Deoxyribose is a modified form of another sugar called ribose. I'm going to give you the structure of that first, because you will need it later anyway. Ribose is the sugar in the backbone of RNA, ribonucleic acid.  DNA structure. DNA is made up of molecules called nucleotides. Each nucleotide contains a phosphate group, a sugar group and a nitrogen base. The four types of nitrogen bases are adenine (A), thymine (T), guanine (G) and cytosine (C). The order of these bases is what determines DNA's instructions, or genetic cod DNA is a double helix formed by base pairs attached to a sugar-phosphate backbone. DNA, or deoxyribonucleic acid, is the hereditary material in humans and almost all other organisms. Nearly every cell in a person’s body has the same DNA. The structure of the double helix is somewhat like a ladder, with the base pairs forming the ladder’s rungs and the sugar and phosphate molecules forming the vertical sidepieces of the ladder. An important property of DNA is that it can replicate, or make copies of itself. The sugar-phosphate supporting structure of the DNA double helix is  called the backbone. This is why the DNA is commonly referred to as  a double helix. 1 person found this useful. 
https://en.wikipedia.org/wiki/DNA http://ghr.nlm.nih.gov/handbook/basics/dna http://djwallis.com/media/BIO/DNA%20Double%20Helix%20KEY.doc http://www.nobelprize.org/educational/medicine/dna_double_helix/readmore.html http://web.stanford.edu/group/hopes/cgi-bin/hopes_test/an-introduction-to-dna-and-chromosomes-text-and-audio/ http://www.nature.com/scitable/definition/double-helix-277 http://www.chemguide.co.uk/organicprops/aminoacids/dna1.html http://www.livescience.com/37247-dna.html http://ghr.nlm.nih.gov/handbook/basics/dna http://www.answers.com/Q/What_is_the_name_of_the_sugar_molecule_in_the_DNA_helix
what is the name of the sugar molecule in the dna helix