2. Venn Diagram Create a Venn Diagram for Food Chain and Food Web Provide at least 3 differences and 3 similar

3. Each ecosystem contains organisms that depend on other organisms for survival. A hierarchy of food relationships from simplest to most complex is called a food chain.

4. Nearly all food webs start with a green plant. Green plants are called producers because they produce their own food. An organism that makes it’s own food, primarily by using sunlight energy in photosynthesis.

5. Animals are consumers. Some consume plants to get the energy they need to live. Others consume other animals. Consumer: an organism that feeds on other organisms (plants or animals) because they cannot make their own food.

6. an organism that breaks down wastes or eats on the dead organisms to provide the soil with nutrients.

7. A food chain consists of 1 producer, 2-3 consumers, and a decomposer. They are found in many types of ecosystems: Land- grass-rabbit-fox-bear (mushroom) River- algae-minnow-bass-human (worms) Ocean plankton-small fish-large fish-shark (worm)

8. Animals that eat plants are called Herbivores. Herbivores have evolved to eat plants. They have specialised teeth and stomachs to enable them to get the energy they need from plants.

9. Animals that eat plants are called Carnivores. Carnivores have evolved to eat meat. They have specialised teeth and stomachs to enable them to get the energy they need from the bodies of other animals.

10. Animals that eat plants and meat are called Omnivores. Humans are omnivores. Omnivores have teeth and stomachs that enable them to eat and digest both plants and meat.

11. Food webs show what eats what in order to gain the energy it needs to live. Food webs use arrows to show what eats what. A food web are many overlapping food chains put together for an entire ecosystem. Eaten by:

12. Food Web Notice that the direction the arrow points  The arrow points in the direction of the energy transfer, NOT “what ate what”

14. Land:

15. Marine

16. Polar Marine:

17. Estuary Food Web:

18. Marine/Land:

19. It is important to realize that food chains and food webs can overlap. When a terrestrial (land- based) food chain overlaps with an aquatic (water-based) food chain, they create a terrestrial-aquatic food web.

20. Energy Pyramid

21. Draw Draw a Pyramid Label with the tropic levels Show the energy transfer and amounts Describe where 90% goes Where would decomposers be located

22. ENERGY FLOW IN ECOSYSTEM How does energy flow in an ecosystem? What is an energy pyramid? What is a trophic level?

23. ENERGY PATHS 3 ways to illustrate energy flow 1. Food Chain: Single path 2. Food Web: many paths 3. Food Pyramid

24. FOOD CHAINS/WEBS & ENERGY PYRAMIDS Food chains/webs can be written as a pyramid: –Producers form the base of the pyramid Consumers form the upper layers Consumers form the upper layers

25. ENERGY PYRAMIDS A level of the energy pyramid is called a TROPHIC LEVEL Each trophic level represents the energy for those organisms Top Consumer Energy stored by Secondary Consumers Energy stored by Primary Consumers ENERGY STORED BY PRODUCERS The energy pyramid shows energy flow in an ecosystem:

26. TROPHIC LEVELS Energy is lost with each trophic –~90% is released to the environment as heat –~10% of the energy is used Only about 10% of the energy from one level is passed on to the next level

28. Trophic Levels—each step in a food chain or food web 1. Level 1—Producers (autotrophs) 2. Level 2—Primary Consumers (herbivores) 3. Level 3—Secondary Consumers (carnivores or omnivores) 4. Level 4—Tertiary Consumers (carnivore—usually top carnivore) 5. Level 5- Quaternary Consumers (carinvore or omnivore)

29. Energy Transfer Energy is used much more efficiently if humans eat plants (first tropic level) instead of meat (second tropic level. A given area of farmland can support more people if the crops are fed directly to people rather than to livestock that people then eat. For example if a man needs 3,000 Calories per day, then 30,000 Cal beef are needed, which in turn need 300,000 Cal of corn, which in turn means 30,000,000 Cal of sunshine. This works out to be 1.5 acres of corn per day per person. If the person ate corn directly then 10 people could be supported by the same 1.5 acres of corn.

30. tertiaryconsumers secondaryconsumers primaryconsumers producers 5 5000 500,000 5,000,000 5,000,000 producers 3.A pyramid of numbers shows the numbers of individual organisms at each trophic level in an ecosystem. 4.A large number of producers are required to support even a few top level consumers.

31. Decomposers: –What is a decomposer and what do they do? What trophic level would you put them at? –Derive their energy from the dead material left by all trophic levels –Are often left off of most food chain diagrams Figure 19.22

32. QUICK REVIEW Practice! If 100% of the energy is available at the first trophic level, what percentages of the energy are available at the second and third trophic levels? 100% 10% 1%

33. QUICK REVIEW! All organisms in an ecosystem need _______ from food to live. An energy ________ shows how much food energy is passed from one ________ to another through food chains. __________ have the largest spot at the base of the pyramid. Altogether, only about _____ of the food energy at each level gets passed up to the next level. energy pyramid Producers 10% organism

34. Summary Questions 1.What does an energy pyramid represent? Why is it the pyramid shape? 2.Where does the energy of a food chain come from? 3.What happens to energy as it gets passed down a food chain? 4.Why can there only be around 5 levels in an energy pyramid? 5.What is one organism that’s important to a food chain that’s not shown on an energy pyramid? Answer on a sheet of paper.