Nutrient & Energy Flow 2.2

I. Producers vs. Consumers A. Producers / Autotrophs- Organisms that can make their own food/sugars. 1. Plants are autotrophs & some bacteria 2. Use light energy, carbon dioxide and water to create sugar and give off oxygen Sun + CO 2 + H 2 O => C 6 H 12 O 6 + O 2 (This is the equation for photosynthesis)

I. Producers vs. Consumers B. Types of Heterotrophs (obtain their food) 1. Herbivore- Eats only plants 2. Carnivore- Eats only other animals 3. Scavenger- Eats only other animals that have already died 4. Omnivore- Eats both plants and other animals =

I. Producers vs. Consumers 5. Decomposer- Break down complex compounds of dead organisms and release nutrients a. Usually bacteria or fungi b. Important for completing the cycle of nutrients c. Used in landfills to speed the rate that wastes get broken down =

II. Trophic Levels A.“Troph” = Food/Energy 1. Explain auto”troph” and hetero”troph” B. Trophic Levels represent the different steps in a food chain or web. 1. Shows how energy is transferred

II. Trophic Levels “ Tertiary Consumers ” Click Here 2 nd – Order Heterotroph Autotroph 1 st - Order Heterotroph 3 rd – Order Heterotroph PRODUCER CARNIVORE HERBIVORE

III. Food Chain vs. Food Web A. Energy and other nutrients that are eaten flow from one organism to the next. B. Food Chain- Simple model that shows how matter and energy move through an ecosystem (one organism to the next) =

III. Food Chain vs. Food Web 1. Autotroph -> Heterotroph -> Decomposer 2. Ex: Berries (autotroph) are eaten by a mouse (heterotroph) who dies and decays (decomposer) 3. Some energy is lost as heat at each level =

III. Food Chain vs. Food Web C. Food Web- Model of ALL possible feeding relationships in a community. 1. More complex than food chains (more realistic, too!) a. See pg. 43 for picture 2. Most organisms do not rely on just one food source =

III. Food Chain vs. Food Web Go outside… 1.Write down one example of a simple food chain that you see. 2.Write down one example of a food web that you see. =

Energy Pipeline Demonstration (Takes entire class period) (Sept. 18, 2008: Lead by guest speaker from Game & Parks) =

IV. Ecological Pyramids A. Ecological pyramids show amounts at each trophic level. 1. See pg. 44for Energy, Numbers and Biomass Pyramids. 2. Notice: the number at each level sometimes goes up, sometimes it goes down. =

IV. Ecological Pyramids B. Test Practice: Study this ecological pyramid. There will be questions on the next slides. Grasshopper Small Bird Snake Large Bird

IV. Ecological Pyramids 1. Which animal will eat the largest numbers of its prey? The small bird will eat many grasshoppers Grasshopper Small Bird Snake Large Bird Hint: What has more calories, steak or salad?

IV. Ecological Pyramids 2. Which level will have the highest concentration of pesticide particles in the digestive tract? Explain. The large bird is highest. The concentration will increase at each level because each animal below eats many of the pesticide-infested animals.

V. Cycles A. Law of Conservation of Mass: Matter is neither created or destroyed. 1. Therefore it must be RECYCLED or we would run out! 2. Matter includes water, carbon, nitrogen, phosphorus, etc. Not true of energy…It is created by the sun and is destroyed all the time!

V. Cycles B. Explain the Water Cycle Below

V. Cycles Feel like doing some theatre? As a class, read the “Water Cycle Play” script for another look at how water is recycled. (Time Permitting)

V. Cycles C.Explain the Carbon Cycle below

V. Cycles 1. Remember that all living things have carbon. We call this “organic.” 2. The “global warming” is caused by raising levels of carbon (CO 2 ) let off by industry? a. For an “other assignment” research the question, “Is global warming really caused by humans?”

V. Cycles D. Nitrogen Fixation- Converting nitrogen gas in the atmosphere to ammonium (nitrogen) compounds in the soil for plant growth 1. Taken up by roots 2. This is done by bacteria in the soil or on the roots a) Ex: soy beans, alfalfa 3. See pg. 48 to study diagram

V. Cycles E. Denitrification- Converting dead organisms into nitrogen gas in the air 1. Done by decomposers

VI. Limiting Factors A. Limiting Factor- Any thing that limits the number of individuals in a population 1. Can be living (biotic) a. Amount of grass available for cattle to graze 2. Can be non-living (abiotic) a. Amount of rain affects how much grass can grow

VI. Limiting Factors 3. Common Limiting Factors a. Food & Water b. Space c. Shelter d. Moisture e. Temperature

VI. Limiting Factors Play “Oh Deer” to simulate and graph how limiting factors affect populations (Time permitting—Takes at least 30 minutes)

VI. Limiting Factors B. Carrying Capacity- The largest number of individuals of one species that the ecosystem can support. 1. Carrying capacity exists because of limiting factors!

VI. Limiting Factors 2. What can we do to INCREASE carrying capacity? a. Plant trees b. Waste less c. Use biotechnology to increase food supply d. Health Care/Medicine

Review What’s the difference between an autotroph and heterotroph? List the 5 kinds of heterotrophs. Give an example of a producer, 1 st, 2 nd, and 3 rd order heterotroph.

Review Give another name for the top consumer in a food chain. What is the difference between a food chain and food web? Why are cycles important on earth?

Review Is energy recycled? Define nitrogen fixation. List three limiting factors in an ecosystem. If there are a lot of limiting factors will the carrying capacity be high or low?