Here's why:

* Organic: Enzymes are proteins, which are complex organic molecules made up of amino acids.

* Catalyst: Enzymes speed up chemical reactions without being consumed in the process.

* Unaffected: While enzymes can change shape during a reaction (induced fit), they return to their original form afterwards, allowing them to catalyze many reactions.

In summary: Enzymes are organic catalysts that speed up chemical reactions in living organisms without being permanently altered themselves.