Unit 08 · Plants, Ecosystems & People
The year closes by placing plants back in the world they feed. This unit covers plants as the primary producers at the base of nearly every food web, primary productivity and the flow of energy through an ecosystem, the roles plants play in the nutrient, carbon, and water cycles, and the human side — agriculture, crops, and food security, plus conservation and biodiversity. Mastery means you can trace energy and matter from sunlight through a plant into an ecosystem, and reason about what happens when people change that flow.
| Criterion | Not yet | Approaching | Mastered |
|---|---|---|---|
| Plants as primary producers | Cannot explain where a food web’s energy begins. | Names producers but not their role at the base of the web. | Explains how plants convert sunlight into the chemical energy that feeds nearly every food web, and places producers at the base. |
| Primary productivity & energy flow | Thinks energy cycles endlessly through an ecosystem. | Describes energy flow but cannot explain loss between trophic levels. | Explains primary productivity and why energy decreases at each trophic level, estimating flow through a simple food chain. |
| Plants in nutrient, carbon & water cycles | Cannot connect plants to any biogeochemical cycle. | Names a cycle but not the plant’s role in it. | Explains how plants move carbon, nutrients, and water through their cycles — from photosynthesis to transpiration to decomposition. |
| Agriculture, food security & conservation | Sees crops and wild plants as unrelated to ecosystems. | Names an issue but cannot weigh a trade-off. | Connects crop production, food security, and biodiversity, and reasons about a conservation trade-off with evidence. |
| Lab technique (field survey & productivity estimate) | Cannot design a survey or take a repeatable measurement. | Collects field data but samples or records loosely. | Runs a seed-dispersal or fruit survey — or a productivity estimate — with a defined method and repeatable measurements. |
| Integration (cross-domain) | Treats the science as isolated facts; makes no cross-domain connection. | Names a link to history, reading, or writing but cannot defend why it matters. | Connects the unit to its anchor across History · Reading · Writing (plus chosen electives) and defends why the connection matters. |
“The plants are the producers, so all the energy starts with photosynthesis; only about a tenth carries to the next level, which is why there are far fewer predators than plants. My quadrat survey estimated productivity for the plot, and I could see how much a crop would draw off that same base.”
“Plants are food for animals. Energy just goes around the ecosystem. I counted some plants but I’m not sure what the number tells me.”
You demonstrate this unit through a field survey and a productivity estimate — sampling seed dispersal or fruit set and reasoning from your data aloud, not a multiple-choice test. A criterion counts as mastered only when you can both run the survey and justify the plant biology behind it. Mastery is demonstrated, not awarded.
A 5-page clipboard packet — unit overview, key terms, the mastery rubric, anchor examples, and a score sheet you can print and grade against.