How It Works

What’s the difference between DNA and RNA?

With the exception of some viruses, all organisms originally store their genetic information as DNA (deoxyribonucleic acid) before making RNA (ribonucleic acid) through a process called ‘transcription’. RNA is then used to make proteins by a process called ‘translation’. Chemically, DNA and RNA both consist of nucleotides linked together. A nucleotide comprises a ribose sugar, a phosphate group and a nitrogenous base. The ribose sugar in DNA is different to that of RNA because it is missing a hydroxyl group (-OH – one oxygen joined to a hydrogen atom). This missing hydroxyl group from DNA makes it less reactive than RNA, making DNA a more stable carrier of genetic information.

Both have bases called adenine, cytosine and guanine; however, DNA has a base called thymine while RNA has a base called uracil, similar to thymine but lacking a methyl group (-CH3 – one carbon atom joined to three hydrogen atoms). DNA is also doublestranded and longer than RNA, usually single-stranded but able to fold back in on itself and catalyse reactions.

Answered by Chi Wing Man.