DNA molecule (down right), computer artwork. DNA (deoxyribonucleic acid) consists of two strands of sugar phosphates forming a double helix (spiral). The strands are linked by nucleotide base pairs (horizontal struts). The sugar-phosphate strands are blue, but highlighted orange at upper right. In this highlighted section, the nucleotide bases are blue. There are four types of nucleotide base found in DNA. The sequence of these bases along the molecule is the genetic code. This DNA genetic code controls growth and development, and it is passed on during reproduction. DNA is found in all living things, and is stored in cell nuclei.