Question

Double helical dna structure and function

Answer 1

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Answer 2

Double helix is the description of the structure of a DNA molecule. A DNA molecule consists of two strands that wind around each other like a twisted ladder.
Each strand has a backbone made of alternating groups of sugar (deoxyribose) and phosphate groups. Attached to each sugar is one of four bases:
•adenine (A),
•cytosine (C),
•guanine (G), or
•thymine (T).
The two strands are held together by bonds between the bases, adenine forming a base pair with thymine, and cytosine forming a base pair with guanine