AP Biology
AP Bio Unit 3 Flashcards
Shared by Ashton · Nov 12, 2026 · 0 plays
44 cards across 5 sections. Flip each card, then say whether you knew it. Cards you miss come back until you know them all.
Sample questions
Open an item to see its answer.
Enzyme
A protein that acts as a biological catalyst: it speeds a reaction by lowering the activation energy. Not used up. ≠ substrate (the molecule it acts on).
Activation energy (Eₐ)
The energy needed to reach the transition state. Enzymes lower it. ≠ ΔG, which enzymes do NOT change.
Active site
The pocket on an enzyme where substrate binds. Its shape AND charge must match the substrate. ≠ allosteric site.
Enzyme–substrate complex
The enzyme with substrate bound in its active site. The model behind 3.1.A.2: shape and charge compatibility.
Substrate
The reactant an enzyme acts on. ≠ product (what's released). Too much product slows the net reaction.