This topic summary covers Knowledge Organiser within Ecosystems Communities for GCSE Biology. Topic 1: Ecosystems Communities It is section 11 of 12 in this topic. Use this topic summary to connect the idea to the wider topic before moving on to questions and flashcards.
Topic position
Section 11 of 12
Practice
15 questions
Recall
20 flashcards
Knowledge Organiser
Key Terms
- Ecosystem: Community of organisms + abiotic environment
- Community: All species in an area
- Population: One species in an area
- Habitat: Where an organism lives
- Niche: Role of an organism in its ecosystem
- Interdependence: Species relying on each other
- Trophic level: Position in a food chain
Abiotic vs Biotic
- Abiotic: Temperature, light, moisture, pH, wind, CO2, O2, minerals
- Biotic: Predation, competition, disease, food availability, new species
- Energy transfer: ~10% between each trophic level
- 90% lost as heat in respiration at each level
Must-Know Facts
- Producers make organic molecules using light energy
- Food chains rarely exceed 4-5 trophic levels
- Removing one species affects the whole community
- Stable communities have balanced predator-prey relationships
- Decomposers recycle nutrients — essential for ecosystem function