The Genome is all the genetic material in the chromosomes. It is made up of 4 molecular units called bases, (represented by the letters C, G, A, T) repeated in different combinations to create unique sections that can make proteins. The units are attached to each other for example A-T and C-G and form a large string with each base pair joining with a complimentary unit. If you imagine the genome as a ladder, the bases form the rungs. The size of the Genome is measured by the total number of these paired bases (bp).