Figure 4: Genomic Structure. The genetic material of a cell is made of deoxyribonucleic acid (DNA) strands, which are composed of
four units called bases (A, T, C, and G). These bases are organized into genes, and the order, or sequence, of these bases provides the
code for producing the various proteins a cell uses to function. The entirety of a person’s DNA is called a genome. It is packaged together
with proteins called histones into thread-like structures called chromosomes. The organization of DNA is similar to the way in which the
letters of the alphabet are carefully ordered to form words and sentences. In this example, the bases form the words that comprise each
verse of the patriotic song, America the Beautiful. The song contains four verses, each representing a gene. In this analogy, the entire
song represents one chromosome, and each of the songs within a songbook would represent a chromosome within the genome.