Food Chains
What Is a Food Chain?
A food chain shows how energy is transferred from one organism to another in an ecosystem through feeding relationships.
💡 Key Concept: Energy flows from producers → primary consumers → secondary consumers → tertiary consumers.
Key Terms to Know
Term | Definition |
Producer | Organism that makes its own food (e.g. plant) using sunlight – photosynthesis |
Consumer | Organism that eats other organisms |
Primary consumer | Herbivore – eats producers (e.g. rabbit) |
Secondary consumer | Carnivore – eats primary consumers |
Tertiary consumer | Carnivore – eats secondary consumers |
Apex predator | Top predator – no natural predators |
Decomposer | Organism that breaks down dead material (e.g. bacteria, fungi) |
Example of a Food Chain
🌱 Grass → 🐰 Rabbit → 🦊 Fox → 🦅 Eagle
✔ Grass is the producer
✔ Rabbit is the primary consumer
✔ Fox is the secondary consumer
✔ Eagle is the tertiary consumer and apex predator
Energy Transfer in Food Chains
✔ Only about 10% of energy is transferred from one trophic level to the next.
✔ Energy is lost through:
- Heat from respiration
- Movement
- Waste (faeces and urine)
- Undigested material
💡 Shorter food chains are more energy efficient.
Pyramids of Biomass
A pyramid of biomass shows the mass of living material at each level in a food chain.
✔ The bottom is always the producer and has the most biomass.
✔ Each level above has less biomass, showing energy loss.
Questions
- What is a producer?
- What does a primary consumer eat?
- Why is only 10% of energy passed on?
- What is an apex predator?
- What do decomposers do?
Summary
- What is a producer?
- What does a primary consumer eat?
- Why is only 10% of energy passed on?
- What is an apex predator?
- What do decomposers do?