DNA is made of chemical building blocks called nucleotides. These building blocks are made of three parts: a phosphate group, a sugar group and one of four types of nitrogen bases. These nucleotides are linked into chains to form a strand of DNA.
The four types of nitrogen bases found in nucleotides are: adenine (A), thymine (T), guanine (G) and cytosine (C). The order, or sequence, of these bases determines what biological instructions are contained in a strand of DNA. They effect everything from what color eyes we have to whether we get certain types of diseases.
Each DNA sequence that contains instructions to make a protein is known as a gene. The size of a gene may vary greatly, ranging from about 1,000 bases to 1 million bases in humans. The complete genome for a human contains about 3 billion bases and about 20,000 genes on 23 pairs of chromosomes.
Three billion bases, and none of it is “junk” (more on this in later posts). This information, stored in our own cells, is all the proof we need of our amazing and creative God!