The molecule responsible for the transformation of characteristics form one generation to the next is called DNA. The genetic material, located in the chromosomes is a combination of acid and histones. DNA is made up of units called nucleotides. Nucleotides are made up of 3 components, a five carbon sugar (deoxyribose), a phosphate group, and a nitrogenous base. This base can be either adenine, guanine, thymine or cytosine. There are 2 strands of nucleotides in a double-helix - they are anti-parallel, meaning they go in opposite directions. Double stranded DNA is located in the chromosome. DNA and proteins together make up chromatin which is foiled and coiled. DNA makes an exact copy of itself