At a glance
Key signals
14% cross fields · reaches 9 more
- Chemistry
- Geography
- Explanation
- Examples
- Misconception
- Sourced relations 4
- Attribution
Dependencies
What this concept builds on and what it makes possible — derived from the atlas’s dependency, causal and structural relations, not from every related edge.
Foundations · builds on
Carbon dioxide (CO₂)is derived fromCellular respirationEstablished
Respiration releases carbon dioxide.
Mechanism: As glucose is broken down, its carbon is released to the air as CO₂ — the reverse of photosynthesis's uptake.
- Campbell Biology — demonstrates this case · verified · moderate evidence · Carbon dioxide is a product of the oxidation of glucose. (9 — Cellular Respiration and Fermentation)
Fossil fuelscausesCarbon dioxide (CO₂)Established
Burning fossil fuels releases carbon dioxide.
Mechanism: Combustion of hydrocarbons combines their carbon with oxygen, emitting CO₂ that photosynthesis had stored long ago.
- IPCC Sixth Assessment Report, Working Group I (Physical Science Basis) — demonstrates this case · needs-check · strong evidence · Fossil-fuel combustion is the dominant driver of the observed rise in atmospheric CO₂. (5 — Global Carbon and other Biogeochemical Cycles and Feedbacks)
Enables · leads to
Ocean acidificationdepends onCarbon dioxide (CO₂)Established
ocean acidification depends on Carbon dioxide (CO₂).
Mechanism: As the ocean absorbs CO₂ it forms carbonic acid, lowering pH and harming shell-building life.
- Wikipedia (English & German editions) verifiedmoderate evidence
PhotosynthesisrequiresCarbon dioxide (CO₂)Established
Photosynthesis requires carbon dioxide.
Mechanism: Carbon dioxide supplies the carbon atoms that are fixed into glucose during the Calvin cycle.
- Campbell Biology — demonstrates this case · verified · moderate evidence · The Calvin cycle fixes atmospheric CO₂ into organic carbon. (10 — Photosynthesis)
System context
Carbon dioxide (CO₂)is part ofAtmosphereEstablished
Carbon dioxide is part of the atmosphere.
Mechanism: CO₂ is one of the trace gases that make up Earth's atmosphere.
- NOAA — The Carbon Cycle (educational resource) — contextual · needs-check · moderate evidence · CO₂ is a trace but climatically decisive constituent of the atmosphere.
Carbonis part ofCarbon dioxide (CO₂)Established
Carbon is part of a carbon dioxide molecule.
Mechanism: A CO₂ molecule is one carbon atom bonded to two oxygen atoms.
- Chemistry 2e (OpenStax) — demonstrates this case · verified · moderate evidence · A carbon dioxide molecule is one carbon atom bonded to two oxygen atoms. (Chemical bonding / molecular composition chapter)
Structural role & consequence
Interpreted from the current atlas graph — what the connections mean, not just how many there are.
14% of its relationships cross field boundaries, reaching 9 other disciplines — unusual in a discipline where most concepts stay within their field.
structural · Structural graph analysis — not a claim of importance, causation or history.
Currently dark in the atlas: no key date stored · 1 of 7 of its relations lack claim-level evidence.
atlas representation · Describes the current Thinking OS representation, not the state of the world.
Builds on 2 foundations (requires / depends-on / derived-from / emerges-from).
structural · Structural graph analysis — not a claim of importance, causation or history.
Structural neighbourhood: 7 → 51 → 165 concepts reachable within 3 hops.
structural · Structural reach — being reachable is not the same as being understood.
cross-field
6 within-field, 1 cross-field
Strengths & constraints
Strengths
- Well-evidenced in the atlas — a verified source and 86% of its relations carry claim-level evidence. atlas representation
Constraints
- No dated history stored — the atlas records no key date for this concept. atlas representation
Conditions
- Its dependency reading rests on 2 foundation relations. structural
Dependency radial
What this concept builds on (left) and what it makes possible (right) — derived from dependency and causal relations.
What builds on this
2 concepts build on this directly, 9 in total, across 11 disciplines.
Structural downstream reach along dependency edges — not a claim of historical necessity.
Seen through each discipline
How this concept sits in each of its fields — derived from its real connections in the graph, not asserted.
Through this lens it connects to Photosynthesis, Cellular respiration, Carbon and Fossil fuels.
Through this lens it connects to Greenhouse effect, Atmosphere and Fossil fuels.
Where you'll meet it
Journeys that walk you through this idea. You may recognise it from more than one.
Related ideas to explore
Concepts that look related but are not yet connected here — candidates for a connection to reason about, not established links.
This idea also appears in…
The same structure shows up in other disciplines. These are real recurrences drawn from the graph — a starting point for asking “what carries over, and what changes?”
Stocks and flows41 disciplines · 36 concepts
Concepts
shares a mental model
shares a mental model
shares a mental model
shares a mental model
shares a mental model
shares a mental model
Curriculum alignment
Austria · AHS Unterstufe (Sekundarstufe I) · Biologie und Umweltbildung
Appears in official curriculum objectives
Understand the structure and function of plant organs and the material transformation in photosynthesis. · 2. Klasse (6. Schulstufe)
Exact wording: „Struktur und Funktion der Pflanzenorgane, Stoffumwandlung bei der Fotosynthese“
How this official objective connects, through canonical knowledge, to what a learner actually does — each link is real data, never a coverage claim.
Canonical concept
- How each concept relates to the objective
- named — The objective's own wording names this concept.
- required — You must grasp this concept to meet the objective.
Relations & mental models
3 canonical relations connect these concepts
- Photosynthesis depends on Light (sunlight)
- Photosynthesis requires Carbon dioxide (CO₂)
- Glucose (sugar) is derived from Photosynthesis
Mental models these concepts carry: Stocks and flows ×3Energy transformation ×2Journey
Journeys that walk concepts relevant to this objective
Activity → Observable evidence
6 activities engage these concepts
identified a missing linkexplained a relationshippredicted an effectpredicted a relationshippredicted a what-if outcomeWhat those activities are designed to make observable — designed intent, not proof of learning.
Provenance
- Authority
- BMBWF
- Document
- BGBl. II Nr. 1/2023
- Section
- Anlage A zu Art. 4 · Biologie und Umweltbildung · Anwendungsbereiche, 2. Klasse (S. 112)
- Version
- Stammfassung, Kundmachung 2. Jänner 2023
- School type
- AHS Unterstufe (Sekundarstufe I)
- Subject
- Biologie und Umweltbildung
- Stage
- lower-secondary
- Accessed
- 2026-09-17
✓ Source verified
Understand the global carbon cycle, CO₂ input into the atmosphere, and climate change. · 4. Klasse (8. Schulstufe)
Exact wording: „Globaler Kohlenstoffkreislauf, CO₂-Eintrag in die Atmosphäre, Klimawandel“
How this official objective connects, through canonical knowledge, to what a learner actually does — each link is real data, never a coverage claim.
Canonical concept
Carbon cycle namedCarbon dioxide (CO₂) namedAtmosphere namedClimate namedGreenhouse effect requiredFossil fuels required- How each concept relates to the objective
- named — The objective's own wording names this concept.
- required — You must grasp this concept to meet the objective.
Relations & mental models
3 canonical relations connect these concepts
- Carbon dioxide (CO₂) amplifies Greenhouse effect
- Carbon dioxide (CO₂) is part of Atmosphere
- Fossil fuels causes Carbon dioxide (CO₂)
Mental models these concepts carry: Feedback loop ×3Stocks and flows ×3ConservationActivity → Observable evidence
5 activities engage these concepts
explained a relationshiptransferred a patternpredicted a relationshippredicted a what-if outcomeWhat those activities are designed to make observable — designed intent, not proof of learning.
“Greenhouse effect” and “fossil fuels” are not named verbatim in this objective, but are the mechanism required to understand it.
Provenance
- Authority
- BMBWF
- Document
- BGBl. II Nr. 1/2023
- Section
- Anlage A zu Art. 4 · Biologie und Umweltbildung · Anwendungsbereiche, 4. Klasse (S. 113)
- Version
- Stammfassung, Kundmachung 2. Jänner 2023
- School type
- AHS Unterstufe (Sekundarstufe I)
- Subject
- Biologie und Umweltbildung
- Stage
- lower-secondary
- Accessed
- 2026-09-17
✓ Source verified
Pilot slice: mapped to selected official objectives, not a coverage claim. Concept identity is canonical and never redefined by a curriculum.
Carbon dioxide is a gas in the air. Plants take it in to make sugar, and it is released when things burn or when living things respire. It also traps heat in the atmosphere.
Mental models at work here
- Connects 7 other ideas across 2 disciplines.
- A cross-disciplinary bridge — its connections reach into 9 other fields.
- Most of its connections are of the “Dependency” kind.
- It exercises 1 reusable thinking pattern.
- It supports 2 curriculum objectives.
- It features in 1 learning journey.
Derived from the graph’s real structure — observations, not a score.
Sources
- NOAA — The Carbon Cycle (educational resource) verification pendingmoderate evidence
- How does elevated carbon dioxide (CO 2 ) affect plant–herbivore interactions? A field experiment and meta‐analysis of CO 2 ‐mediated changes on plant chemistry and herbivore performance (2007) verified
- Synthesis and characterization of poly(styrene-co-butyl acrylate) and poly(styrene-co-butyl methacrylate) in supercritical carbon dioxide (2004) verified
- Carbon Dioxide (CO) (2007) verified