Ribonucleic acid (RNA), generally abbreviated RNA, is an organic chemical substance in living cells that plays several essential roles in the transfer of genetic information from one generation to the next. The hereditary information itself is contained in a similar organic substance known as deoxyribonucleic acid (DNA). RNA is what enables this genetic information to be copied from the parent's DNA and inherited by the offspring.

Both RNA and DNA are nucleic acids, so called because they are found in cell nuclei. (RNA is also found in other parts of the cell.) Nucleic acids are the storehouse and delivery system of our genetic traits. The actual biological processes that they prescribe are carried out mostly by our proteins--our enzymes, hormones and muscles. In other words, nucleic acids are the instruction manual for life's protein-built operating equipment. Each nucleotide monomer molecule consists of a sugar...