Step-by-step explanation:
DNA WHICH STANDS FOR DEOXYRIBONUCLEIC ACID ,RESEMBLES ALONG,SPIRALING LADDER . IT CONSISTS OF JUST A FEW KINDS OF ATOMS :CARBON,HYDROGEN ,OXYGEN ,NITROGEN ,AND PHOSPHORUS.
COMBINATIONS OF THESE ATOMS FORM THE SUGAR --- PHOSPHATE BACKBONE OF THE DNA--THE SIDES OF THE LADDER ,IN OTHER WORDS.