.food chains & food webs.

1. .food chains & food webs. ISN page 169.

2. 169 food chains & food webs • Food Chain • Food Web • Arrows? • Producers • Consumers • Primary • Secondary • Tertiary • Pyramid of Biomass • Rule:

3. Food Chain • A simple diagram that shows one part of an ecosystem. • Transfer of energy from one organism to another

4. What is a food web? • Shows the interactions of predators and prey in an ecosystem

5. What do the arrows indicate in a food web? • They indicate the flow of energy from one organism to another. • If a worm is eaten by a robin, does the arrow point to the worm or the robin?

6. Producers make their food from the sun’s energy. They are also called autotrophs. • Name 2 producers • Algae, bladderwrack

7. Primary consumers eat producers. They are also called heterotrophs or herbivores. • Name 3 primary consumers. • Grey mullet, flat winkle, limpet, sea urchin

8. Secondary consumers eat primary consumers. They are also called carnivores. • Name 3 secondary consumers. • Crab, seal, lobster, herring gull

9. Tertiary consumers eat secondary consumers. • Are there any? • Yes…….seal, herring gull

10. Pyramid of Biomass • BIOMASS: how much a population of organisms weighs • The greatest amount of biomass is found in the producers. • The least amount in the tertiary consumers.

11. 10% Rule: Only 10% of the available energy passes on to the next trophic level

12. food chains & webs

13. Food Web Practice: 170 • Identify the: • 1. Producers • 2. Primary Consumers • 3. Secondary Consumers • 4. Herbivores • 5. Carnivores • 6. Omnivores • 7. What elements are missing from this food web?

15. ECOSYSTEMS NOTES 1. What happens to matter within a food chains? 2. What happens to energy within a food chain? 3. In a pyramid of numbers, what would you not expect to find ? 4. What is the carbon cycle? 5. What is a niche? Give an example. 6. What is an abiotic factor of an ecosystem? 7. What are ecosystems based on? 8. What do food producers need to make sugar?