Here you can see how the bases of a helix become a DNA sequence.
When you write a letter, you put together words using different letters of the alphabet. With twenty-six letters you can say anything you want. It is important that the letters go in the right order. This sentence stops making sense whenthaliekrnviserhflker
are in the wrong order.
When you make new cells, your body is putting together different letters of the DNA alphabet.
Even with just four letters, the DNA alphabet spells out all of the information you need to create new cells and to stay healthy. The order of the DNA bases is called the sequence. Just like the order of the letters in a sentence, the sequence of the bases in DNA can spell all the instructions for your body -- even with only four letters.