Question

The codons (words) in DNA that identify which amino acid should be in a protein are three bases long. How many such three-letter words can be made from the four bases adenine, cytosine, guanine, and thymine?

Short answer

There are 64 different three-letter words.

Step-by-step solution

The given bases

The given bases are adenine, cytosine, guanine, and thymine. The following three-letter words are possible:

Explanation

There are three bases in one code. It is available four different options (bases) per position in code. Each position in code has four possibilities (each base). Therefore, the formula will be ( $\text{4}\times \text{4}\times \text{4 = 64}$).

Hence, there are 64 different three-letter words.