What is the difference between dna and rna

DNA there are 2 chains parallel to each othe
RNA is only one and copies the ADN

DNA contains the sugar deoxyribose, while RNA contains the sugar ribose. The difference between ribose and deoxyribose is that ribose has one more   -OH group than deoxyribose, in which has -H attached to the second (2') carbon in the ring. DNA is a double-stranded molecule while RNA is a single stranded molecule. DNA is stable under alkaline conditions while RNA is not stable. DNA and RNA perform different functions in humans. DNA is responsible for storing and transferring genetic info while RNA directly codes for amino acids and as acts as a messenger between DNA and ribosomes to make proteins. DNA and RNA base pairing are a little different since DNA uses the bases adenine, thymine, cytosine, and guanine; RNA uses adenine, uracil, cytosine, and guanine. Uracil differs from thymine in that it lacks a methyl group on its ring. I hope this answer has helped you in some way, and that there is more than one answer to how DNA and RNA are different. I listed as much as I could find. 

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