Why 20 amino acids instead of 64?

There are 20 amino acids instead of 64 because not every group needs a unique messenger, it’s like having fewer helpers for more jobs.

Imagine you're building a robot with blocks, and each block has a color. You have 64 different colors to choose from, but most robots only need about 20 special kinds of blocks to do all their tasks. That way, the robot doesn’t get confused by too many choices, it just uses the ones that work best.

Think of amino acids as those colored blocks. There are 64 different messages (called codons) that DNA can send, but only 20 unique amino acids are needed to build proteins. That’s because some messages tell the robot to use the same block, it’s like having two different notes saying “use a red block,” even though they’re written differently.

It's like having twins who both know how to tie their shoes, you don’t need separate instructions for each one. Some amino acids are used by multiple codons, which makes the whole system more efficient and less complicated.

So, 20 amino acids work better than 64 because they’re shared helpers in a busy robot factory!