Across
- 1. mesophyll layer – Upper layer of leaf cells packed with chloroplasts; major site of photosynthesis.
- 3. A – Molecule that helps convert pyruvate into acetyl-CoA for the Krebs cycle.
- 4. – A 5-carbon molecule that binds CO₂ to begin the Calvin cycle.
- 8. – Waxy outer layer of leaves that reduces water loss.
- 12. cell – Specialized cells around stomata that regulate their opening and closing.
- 13. – Fluid-filled space around the grana; site of the Calvin cycle.
- 14. (G3P) – A 3-carbon sugar produced in the Calvin cycle; used to form glucose.
- 16. – Flattened membrane sacs containing chlorophyll; site of light reactions.
- 19. – An organism that produces its own food, usually via photosynthesis or chemosynthesis.
- 20. factors of photosynthesis – Light intensity, CO₂ concentration, temperature, and water availability.
- 24. acid fermentation – Anaerobic process in animals that converts pyruvate to lactic acid and regenerates NAD⁺.
- 27. II (PSII) – First photosystem; splits water and drives ATP formation.
- 31. spectrum – Range of wavelengths of light absorbed by pigments.
- 32. – Electron carrier that becomes NADPH when reduced.
- 34. Cycle – Light-independent reactions that convert CO₂ into sugars in the stroma.
- 36. – Enzyme that fixes CO₂ to RuBP; the most abundant enzyme on Earth.
- 37. – Electron carrier used mainly in photosynthesis.
- 38. respiration – Cellular respiration that requires oxygen; produces large amounts of ATP.
Down
- 1. – Wasteful process where Rubisco binds O₂ instead of CO₂, reducing photosynthetic efficiency.
- 2. aerobes – Organisms that require oxygen to survive.
- 5. I (PSI) – Uses light to energize electrons; helps produce NADPH.
- 6. respiration – Respiration without oxygen; includes fermentation pathways.
- 7. – An organism that must obtain food/energy by consuming other organisms.
- 9. plants / C4 photosynthesis – Fix CO₂ into 4-carbon molecules to avoid photorespiration (e.g., corn).
- 10. cycle – Second stage of aerobic respiration; breaks down acetyl-CoA, producing CO₂, NADH, FADH₂, and ATP.
- 11. aerobes – Organisms that can live with or without oxygen.
- 12. – First stage of respiration; breaks glucose into 2 pyruvate molecules, producing 2 ATP and NADH.
- 15. – Electron carrier that becomes FADH₂ when reduced.
- 17. (stoma) – Pores on leaf surfaces for gas exchange (CO₂ in, O₂ and water vapor out).
- 18. – Electron carrier produced in glycolysis and Krebs cycle.
- 21. (granum) – Stacks of thylakoids.
- 22. fermentation – Anaerobic process in yeast producing ethanol, CO₂, and NAD⁺.
- 23. transport system (ETS) – Chain of proteins in thylakoid membranes that pass electrons, creating ATP.
- 25. plants / C3 photosynthesis – Use the standard Calvin cycle; most common plants.
- 26. – Electron-carrying proteins in the electron transport chain.
- 28. mesophyll layer – Loosely arranged cells with air spaces; allows gas exchange.
- 29. – Loss of water vapor from plant leaves through stomata.
- 30. – The main energy-carrying molecule used by cells.
- 33. plants / CAM photosynthesis – Open stomata at night; store CO₂ for daytime photosynthesis (e.g., cacti).
- 35. acid (pyruvate) – End product of glycolysis; enters fermentation or the Krebs cycle.