The Sequence Decides Everything

A protein is a string of amino acids in a specific order — and that order is not the shape. It is the instruction for the shape. Watch the chain fold: the backbone hydrogen-bonds to itself into helices and sheets, the R-groups pull the whole thing into a compact 3-D form, and only then does the molecule do a job. Then watch it come apart in a frying pan — and watch every peptide bond survive, which is the one thing students never believe.

AP BIOLOGY · 8 STEPS · 6 QUICK CHECKS · 1° → 2° → 3° → 4° · SEQUENCE DETERMINES FOLD · DENATURING KEEPS THE SEQUENCE · v1