Answer:
The backbone of the double helix is made up of SUGAR molecules and PHOSPHATE groups, and the two chains are joined together by hydrogen bonds between the NUCLEOTIDE BASES
Explanation:
DNA is a double helix structure. It looks similar to a twisted ladder. The backbone is like the sides of the ladder. They are made up of sugar molecules called deoxyribose and phosphate linked together. The nucleotide bases make up the rungs. Each rung is made up of 2 complimentary bases that are held together by hydrogen bonds.
