Carbon cycles through living and non-living stores
| English | 中文 | Pinyin |
|---|---|---|
| decomposer/ˌdiːkəmˈpəʊzə/ | 分解者 | fēn jiě zhě |
| carbon cycle/ˈkɑːbən ˈsaɪkl/ | 碳循环 | tàn xún huán |
What would explain this observation?
- Carbon in a leaf can enter an animal, a decomposer 分解者 or the air. A cycle traces atoms through several routes rather than one compulsory sequence.
- Start with a prediction. State the quantities or features you would compare, then decide what evidence could distinguish two explanations.
Build the model
- Photosynthesis takes carbon dioxide from the atmosphere into organic molecules in producers. Feeding transfers carbon-containing molecules to consumers. Plants, animals and microorganisms respire, releasing carbon dioxide. Decomposers break down dead material and waste; their respiration returns carbon dioxide and mineral ions return to the soil through decomposition.
- carbon cycle 碳循环: Transfers returning carbon through living and non-living components; decomposer: An organism breaking down dead organic material and waste.
Which process returns carbon dioxide from a plant to the air?
Carbon can remain in organic stores, including fuels formed over long periods. Combustion releases carbon dioxide from carbon-containing fuels or biomass. Materials cycle between biotic and abiotic components and provide building blocks for later organisms. Energy transfers through the system rather than being recycled in the same way.
Match each technical term to its precise meaning.
Use the definitions to distinguish related quantities and processes.
Choose evidence that can test it
- Carbon can remain in organic stores, including fuels formed over long periods. Combustion releases carbon dioxide from carbon-containing fuels or biomass. Materials cycle between biotic and abiotic components and provide building blocks for later organisms. Energy transfers through the system rather than being recycled in the same way.
- Interpret a cycle diagram by naming the process at each arrow. Identify alternative routes out of a living organism: feeding, respiration or death and decomposition. Use stated stores and transfers in a mass balance; do not confuse a carbon amount with a carbon-dioxide volume unless a conversion is given.
Which two habits make the investigation or model in this case more defensible?
Interpret a cycle diagram by naming the process at each arrow. Identify alternative routes out of a living organism: feeding, respiration or death and decomposition. Use stated stores and transfers in a mass balance; do not confuse a carbon amount with a carbon-dioxide volume unless a conversion is given.
Work from known quantities
- State the known values and their units. Choose the relation because its assumptions fit this case, then rearrange before substitution.
- Known: in a closed fictional carbon account, plants gain 50 carbon units by photosynthesis, transfer 18 by feeding and release 12 by respiration during one interval. Net plant-store increase = 50−18−12 = 20 units, with all other transfers explicitly excluded. This is a store balance, not an energy-efficiency calculation.
A model plant store gains 70 carbon units and loses 24 by feeding and 16 by respiration. Find net increase. Use the same sequence: known quantities → model → relation → substitution → unit and interpretation.
A model plant store gains 70 carbon units and loses 24 by feeding and 16 by respiration. Find net increase.
The result is 30 carbon units. Known: in a closed fictional carbon account, plants gain 50 carbon units by photosynthesis, transfer 18 by feeding and release 12 by respiration during one interval. Net plant-store increase = 50−18−12 = 20 units, with all other transfers explicitly excluded. This is a store balance, not an energy-efficiency calculation.
Check the conclusion and its limits
- Plants both photosynthesise and respire. Decomposition does not make carbon disappear. Not every arrow goes from one organism to the next trophic level, and the nitrogen cycle is not required by this specification section.
- Return to the original observation. Explain what the result supports, which conditions it assumes, and one way to test a competing explanation.
Plants never release carbon dioxide by respiration. This claim is false: Plants both photosynthesise and respire. Decomposition does not make carbon disappear. Not every arrow goes from one organism to the next trophic level, and the nitrogen cycle is not required by this specification section.
Carbon cycles through living and non-living stores: Carbon can remain in organic stores, including fuels formed over long periods. Combustion releases carbon dioxide from carbon-containing fuels or biomass. Materials cycle between biotic and abiotic components and provide building blocks for later organisms. Energy transfers through the system rather than being recycled in the same way.
Plants never release carbon dioxide by respiration.
Plants both photosynthesise and respire. Decomposition does not make carbon disappear. Not every arrow goes from one organism to the next trophic level, and the nitrogen cycle is not required by this specification section.
Transfers returning carbon through living and non-living components: write the technical term.
carbon cycle means Transfers returning carbon through living and non-living components.