EcologyComparison
Nitrogen Cycle vs Carbon Cycle
Part of The Nitrogen Cycle · GCSE GCSE Biology revision
This comparison covers Nitrogen Cycle vs Carbon Cycle within The Nitrogen Cycle for GCSE Biology. The nitrogen cycle: nitrogen-fixing, nitrifying, denitrifying bacteria, ammonification, and the role of legumes It is section 6 of 14 in this topic. Use this comparison to connect the idea to the wider topic before moving on to questions and flashcards.
Topic position
Section 6 of 14
Practice
15 questions
Recall
15 flashcards
⚖️ Nitrogen Cycle vs Carbon Cycle
Figure 2: Comparing the nitrogen cycle and carbon cycle — different elements, different key organisms, different processes.
| Feature | Carbon Cycle | Nitrogen Cycle |
|---|---|---|
| Element cycled | Carbon (C) | Nitrogen (N) |
| Main atmospheric form | CO₂ (0.04%) | N₂ (78%) |
| How plants access it | Directly as CO₂ via stomata | As nitrates via roots (bacteria convert N₂ first) |
| Key process removing it from atmosphere | Photosynthesis | Nitrogen fixation (by bacteria) |
| Key process returning it to atmosphere | Respiration, combustion, decomposition | Denitrification (by bacteria) |
| Role of bacteria | Decomposition only (releases CO₂) | Essential at EVERY stage (fixation, nitrification, ammonification, denitrification) |
| What it is used for in organisms | Energy (respiration), structure (glucose, starch, cellulose) | Proteins, DNA, chlorophyll |
| Human impact | Fossil fuel burning increases atmospheric CO₂ | Fertiliser overuse leaches nitrates into waterways (eutrophication) |