Commonly confused

Pepsin vs Trypsin

The tell

Pepsin works in the stomach at pH ≈ 2 and is activated by HCl. Trypsin works in the duodenum at pH ≈ 8, is activated by enteropeptidase, and arms all the other pancreatic zymogens.

Pairs like this are where exam points go missing — the concepts are fine, the labels swap. Retrieval fixes it faster than rereading: the daily quiz mixes confusable pairs into every set.

Today’s daily quiz All confusable pairs