AP Biology Unit 3 flashcards
Fifteen cards on Cellular Energetics — the facts this unit is actually tested on: enzyme structure and inhibition, the laws of thermodynamics in cells, glycolysis, the Krebs cycle, the electron transport chain and chemiosmosis, the light reactions and the Calvin cycle. Read them here, no sign-up. When you want cards from your own class notes instead of someone else's, paste them into FlashDeck and you have a deck in seconds.
Last updated: 24 September 2026
The AP Biology Unit 3 deck
| Question | Answer |
|---|---|
| What is the primary function of enzymes in biological reactions? | They act as catalysts that lower activation energy, speeding up reactions without being consumed. |
| What is the active site of an enzyme? | The specific region where the substrate binds and catalysis occurs. |
| How does a competitive inhibitor affect enzyme activity? | It binds to the active site, blocking substrate binding; inhibition can be overcome by increasing substrate concentration. |
| How does a noncompetitive inhibitor affect enzyme activity? | It binds to an allosteric site, changing enzyme shape and preventing catalysis; not overcome by adding substrate. |
| State the first law of thermodynamics. | Energy cannot be created or destroyed, only transferred or transformed. |
| State the second law of thermodynamics. | Every energy transfer or transformation increases the entropy of the universe. |
| Is ATP hydrolysis endergonic or exergonic? | Exergonic; it releases energy used to drive cellular work. |
| Where does glycolysis occur and what are its net products? | Cytoplasm; net 2 ATP, 2 NADH, and 2 pyruvate per glucose. |
| Where does the Krebs cycle occur? | In the mitochondrial matrix. |
| What are the net products of the Krebs cycle per glucose? | 2 ATP, 6 NADH, 2 FADH2, and 4 CO2 per glucose. |
| Where is the electron transport chain located in eukaryotes? | In the inner mitochondrial membrane. |
| What is the role of the electron transport chain? | It transfers electrons to oxygen, pumping protons to create a gradient. |
| How is ATP synthesized in chemiosmosis? | Protons flow through ATP synthase down their gradient, driving ATP production. |
| Where do the light reactions occur and what do they produce? | Thylakoid membranes; ATP, NADPH, and oxygen (O2). |
| Where does the Calvin cycle occur and what does it produce? | In the chloroplast stroma; uses ATP, NADPH, CO2 to produce G3P/sugar. |
How to actually remember these
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Other AP Biology units
AP Biology Unit 1 · AP Biology Unit 2
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