DNA's code

What is DNA's alphabet?

We use codes everyday; alphabets are also codes. Let's take the word "koala". In English, the letters 'k', 'o', 'a', 'l' and 'a' in that particular order mean an animal that lives in Australia and eats eucalyptus leaves. If you didn't know any English, you wouldn't be able to guess what the word means from the letters that are in it. The letters 'k', 'o', 'a', and 'l' appear in lots of other words where they don't mean anything to do with koalas. Different languages use different alphabets to convey meaning.

DNA's code is written in only four 'letters', called A, C, T and G. The meaning of this code lies in the sequence of the letters A, T, C and G in the same way that the meaning of a word lies in the sequence of alphabet letters. Your cells read the DNA sequence to make chemicals that your body needs to survive.