Tuesday, August 23, 2016

Transcription

1 Tuesday, August 23, Add to your table of contents: Date Activity Evidence # 8/23/16 Food Webs/Energy Transfer 5 2.Complete the bellwork and copy today s objective onto evidence #5.

2 Autotroph/Producer Make their own food using the process of photosynthesis (converting sunlight and carbon dioxide into glucose and oxygen). All of the energy required to begin this process comes from the sun. Autotrophs are also called Producers. All other organisms get their energy from producers. Without autotrophs, there would be no life on this planet Ex. Plants and Algae

3 Heterotrophs Do not make their own food, but instead consume other organisms to survive. Another term for Heterotroph is Consumer. Ex. Rabbits, Deer, Mushrooms

4 Heterotrophs - Consumers 1. Scavengers/Detritivores feed on the tissue of dead organisms (both plants and animals) Ex. Vultures, Crows, and Shrimp

5 Heterotrophs - Consumers 2. Herbivores eat ONLY plants Ex. Cows, Elephants, Giraffes

6 Heterotrophs - Consumers 3. Carnivores eat ONLY meat Ex. Lions, Tigers, Sharks

7 Heterotrophs - Consumers 4. Omnivores eat BOTH plants and animals Ex. Bears and Humans

8 Heterotrophs - consumers 5. Decomposers absorb any dead material and break it down into nutrients found in the soil **Decomposers can appear at any point in a food chain whenever and organism dies. Ex. Bacteria and Mushrooms

9 Food Chains Series of events in which one organism eats another and obtains energy. Each level is called a trophic level. It involves one organism at each trophic level Primary Consumers eat producers/plants and can be omnivores or herbivores Secondary Consumers a omnivore or carnivore that eats the primary consumer Tertiary Consumers eats secondary consumer; often called the top of the food chain

10 Food Chains Draw the example on each level of your food chain in your notes.

11 Trophic Levels Energy moves from one organisms to another when it is eaten Each step in this transfer of energy is know as a trophic level Remember that all energy in an ecosystem originally comes from the Sun. It begins each food chain.

12 Transfer of Energy When a grasshopper eats the grass, it does not obtain all of the energy the grass has (much of it is not eaten) When a snake eats the grasshopper, it does not get all of the energy from the grasshopper (much of it is lost as heat) When a hawk eats the snake, there s an even smaller amount of energy that s transferred

13 Transfer of Energy These are examples of energy transfer that show that no organism EVER receives all of the energy from the organism they just ate Only 10% of the energy from one trophic level is transferred to the next this is called the 10% law

14 Food Webs Most organisms eat more the JUST one organism Several overlapping food chains in an ecosystem make up a food web.

15 Food Webs Notice the direction the arrow points The arrow points in the direction of the energy transfer, NOT what ate what

16 Food Webs

17 Energy Pyramid An energy pyramid shows the relationship between consumers and producers at different trophic levels in an ecosystem Shows the relative amounts of energy or matter contained at each trophic level The Pyramid shows which level has the most energy and the highest number of organisms

18 Energy Pyramid The amount of available energy and the number of organisms decreases as you move up the pyramid.

19 M&M food chain game 1. You were given a card that states either Producers (or autotroph), Primary consumer (or heterotroph), or Predator (or secondary consumer). 2. Producers get 15 M&Ms. 3. Primary consumers must go around and take 6 M&Ms from two Producers (don t take it from a producer that has already had 6 taken) 4 Predators must go around and take 3 M&Ms from three Primary Consumers (don t take it from a consumer that has already had 3 taken)

20 M&M food chain game Everyone should now have 9 M&Ms which are representing energy Reflect on the following questions in your science notebook: 1. What happened to the amount of energy that transferred during each step? 2. In which step would it require the most energy to get the food needed for survival? 3. Which trophic level (producer, primary, secondary, or tertiary) is the most inefficient and why?