Nucleic Acids

Every organism resembles its parents and ancestors in many ways — this transmission of inherited characters from one generation to the next is called heredity. The task of carrying this hereditary information falls to structures inside the nucleus of a living cell called chromosomes, which are built from two kinds of biomolecules: proteins and nucleic acids.

Nucleic acids are of two types:

• Deoxyribonucleic acid (DNA)
• Ribonucleic acid (RNA)

Both are found chiefly in the nucleus of the cell. Structurally, a nucleic acid is a very long chain built from repeating units called nucleotides, so nucleic acids are also known as polynucleotides.

Together, DNA and RNA are responsible for two connected jobs central to the chemistry of life:

• storing and passing on hereditary (genetic) information from parent to offspring, and
• directing the synthesis of proteins inside the cell. …