🧾 5-Minute Cram Sheet
Read this right before walking into the test.
⚡ Photosynthesis
- Happens in chloroplasts (light reactions → thylakoid; Calvin → stroma).
- Inputs: CO₂, H₂O, light. Outputs: glucose, O₂.
- Stores energy.
6 CO₂ + 6 H₂O + light → C₆H₁₂O₆ + 6 O₂
🔥 Cellular Respiration
- Glycolysis → cytosol.
- Krebs → mitochondrial matrix.
- ETC → inner mitochondrial membrane (most ATP here).
- All living things do it. Plants too.
C₆H₁₂O₆ + 6 O₂ → 6 CO₂ + 6 H₂O + ATP
♻️ Carbon Cycle
- Photosynthesis pulls CO₂ OUT of air.
- Respiration, decomposition, combustion put CO₂ BACK.
- Burning fossil fuels = fast carbon release → climate change.
🌱 Nitrogen Cycle
- N₂ (78% of air) is unusable to plants/animals.
- Bacteria do everything: fix N₂ → NH₃ → NO₃⁻; denitrify NO₃⁻ → N₂.
- Plants absorb nitrates from soil; animals eat plants.
🌍 Ecology
- Roles: producers (plants) → 1°/2°/3° consumers → decomposers (recycle).
- 10% rule: only 10% of energy passes up each level.
- Energy flows; matter cycles.
- Levels: organism → population → community → ecosystem → biome.
- Symbiosis: mutualism (+/+), commensalism (+/0), parasitism (+/−).
- Biodiversity = stability.
🧩 Cells & Systems
- Form follows function (RBC: no nucleus → more O₂; muscle: many mitochondria).
- Homeostasis = stable internal conditions (sweat, insulin, kidneys).
🧬 Genetics
- DNA (molecule) → Gene (section) → Chromosome (bundle).
- DNA → mRNA → Protein → Trait.
- Sexual repro = variation; asexual = clones (fast).
- Mutations = source of new variation. Mostly neutral.
🦖 Evolution
- 4 steps: Variation → Competition → Survival → Reproduction.
- Populations evolve. Individuals do NOT.
- Evidence: fossils, homologous structures, DNA, embryology.
You've got this, Maraki. ✨
Trust the patterns. When in doubt: energy flows, matter cycles, populations evolve.