Safety and evidence boundary
Use supplied ecological datasets, safe non-contact observation, and paper/digital food-web models. Do not disturb wildlife or reveal sensitive species locations. Energy-flow models are ecosystem approximations and should include units, area/time scales, and uncertainty.
Explicit science instruction
Ecosystem energy flow links photosynthesis, respiration, biomass production and feeding. Energy captured by producers becomes chemical energy, much is used in metabolism, and a fraction enters consumer biomass. Decomposers process dead organic matter but do not recycle energy back into sunlight.
Worked example with reasoning
GPP/NPP calculations establish producer energy supply; transfer efficiencies track consumer production; a food web identifies pathways. Together they explain why upper trophic levels have less production available.
Guided question
How does cellular respiration help explain the shape of an ecosystem energy pyramid?
Independent work
- Write a Week 31 CER.
- Use one NPP calculation, two efficiencies and one indirect food-web effect.
- Contrast energy flow with matter cycling.
- State one model limitation.
Spiral retrieval bridge
Try these from memory before reopening earlier lessons. Then check your reasoning and record one correction if needed.
- From Week 9: distinguish the matter source for sugar from the energy source driving photosynthesis.
- From Week 10: how does respiration help explain why trophic transfer is less than 100%?
- Calculate ecological efficiency when 500 kJ of consumer production follows 5,000 kJ of producer production.
- Correct this statement: “Decomposers recycle energy back to producers.”
Retrieval is formative. The goal is durable connection across units, not a separate grade.
Misconception check
Decomposers recycle matter, not usable energy back to producers. Energy ultimately dissipates while elements can re-enter cycles.
Formative understanding check
What is the central difference between energy and matter in ecosystems?
Worked response
Energy flows and dissipates; matter is transferred and recycled among reservoirs.
Open-book formative practice only; not an official mastery attempt or grade.
Mentor evidence conference
Ask Archaemenes to challenge your model topology, evidence classification, calculation, and stated uncertainty without substituting belief or protected answers for science mastery.
Open ArchaemenesTeacher guidance
Foundation: use a cross-scale diagram. Core: integrate cellular and ecosystem energetics. Extended: quantify how alternative efficiencies change top-level production.
Preserve learning evidence
Keep models, data work, corrections, source classifications, and limitations in the matching Week 31 evidence field.