Study guide: Photosynthesis, Decomposition and Resources
Extend food-chain learning with plant food-making and decomposition.
Ideas to explain in your own words
- Green plants use light energy to build sugars from water and carbon dioxide. Much plant mass comes from air carbon, not from eating soil. This simplified model omits many steps.
- Plants make food molecules but also need mineral nutrients. Soil is a source of water and minerals, not a meal. Fertilizer does not replace light, water or carbon dioxide.
- Decomposers break down dead material and wastes, returning matter to surroundings. Matter cycles, while energy eventually disperses as heat. A decomposer is not merely a predator eating live prey. Decomposers are also consumers broadly because they obtain organic food; the specific alternatives here distinguish their feeding role from a herbivorous animal.
- Resource decisions can affect living systems through several paths. Name the supplied mechanism and avoid assuming a single action fixes every effect. Models support conditional claims.
Useful vocabulary
- carbon dioxide
- carbon-containing input from air
- food molecule
- sugar containing stored chemical energy
- decomposer
- organism breaking down dead material
- water effect
- changes available water
Watch your reasoning
- Check what carbon dioxide and water each mean. They describe different clues.
- Check what food molecule and mineral nutrient each mean. They describe different clues.
- Check what decomposer and producer each mean. They describe different clues.
A worked review example
Worked reference-card problem: a card states “carbon-containing input from air”; a second states “input taken up from surroundings.” The first fits carbon dioxide and the second fits water. The reason is the described function or change, not the order of the cards or a favorite name. If their descriptions exchange places, their category labels exchange too. Keep the supplied descriptions attached to the correct case. Worked reference-card problem: a card states “sugar containing stored chemical energy”; a second states “needed nonfood nutrient from surroundings.” The first fits food molecule and the second fits mineral nutrient. The reason is the described function or change, not the order of the cards or a favorite name. If their descriptions exchange places, their category labels exchange too. Keep the supplied descriptions attached to the correct case. Worked reference-card problem: a card states “organism breaking down dead material”; a second states “organism making food from simpler inputs.” The first fits decomposer and the second fits producer. The reason is the described function or change, not the order of the cards or a favorite name. If their descriptions exchange places, their category labels exchange too. Keep the supplied descriptions attached to the correct case. Worked reference-card problem: a card states “changes available water”; a second states “changes living space or cover.” The first fits water effect and the second fits habitat effect. The reason is the described function or change, not the order of the cards or a favorite name. If their descriptions exchange places, their category labels exchange too. Keep the supplied descriptions attached to the correct case.
Make a practice plan
- Use an example from Identify photosynthesis inputs and outputs. Say what happens and point to the clue that helps explain it.
- Complete Separate food and minerals and correct the specific misconception in its feedback.
- Resolve a changed case from Describe decomposition, then combine the four ideas in the transfer task.