RNA: animation of a highly simplified model of single stranded RNA molecule. KEY:

RNA or ribonucleic acid stores information in the sequence of bases that project from the sugar-phosphate backbone. It can occur as single strands (e.g. in messenger RNA) as a complicated folded molecule (as in transfer RNA) or combined with proteins (e.g. in ribosomes).

RNA differs from DNA in that the RNA sugar (ribose) contains an extra oxygen (as an hydroxyl group projecting from 2'C) and that the base thymidine (in DNA) is replaced by the base uracil (in RNA). Uracil differs from thymidine in having a CH3 group missing. The DNA sugar is named as ribose lacking an oxygen hence deoxyribose. The additional hydroxyl group on ribose makes the RNA molecule more prone to hydrolysis and alters the way the molecule structures itself. The greater stability of DNA makes it more suited to long term data storage (i.e. it is better suited to house the genome). RNA (as messenger RNA) carries information from the nucleus (info. stored in genomic DNA) and out into the cytoplasm where it instructs protein synthesis. Protein synthesis involves other types of RNA as well. Transfer RNA (tRNA) latches on to amino acids and transfers them to the ribosome (also made of RNA) where protein assembly takes place.

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