Ch 18-2
Make a list of everything that you ate yesterday. Next to each item, write where it comes from (Hint: list plant or animal).
Write EQ’s How is energy transferred within an ecosystem? How are the four energy roles different from each other? Why is only 10% of the energy passed to the next level in the energy pyramid?
Use food webs to describe how energy and matter are transferred from one organism to another. Trace the transfer of matter in a food chain and food web.
Where do you get your energy from? Where do animals get their energy from? Where do plants get their energy from?
Ecologists study feeding patterns to learn how energy flows within an ecosystem.
Each organism has a different role in the movement of energy through its ecosystem.
Energy role determined by ◦ how it obtains energy ◦ how it interacts with the other living things
* Energy enters most ecosystems as sunlight and is converted through photosynthesis
Photosynthesis= the process by which photoautotrophs (plants and some other organisms) capture light energy and use it to make food(sugars) from carbon dioxide and water.
s/images/csi/nur04506.jpg chemoautotrophs convert chemicals to energy in the deep ocean and dark caves Bacteria break down the sulfur compounds to release the energy.
Reactants are what goes in…. 6CO H 2 O + sunlight Six molecules of carbon dioxide (CO 2 ) Plus Six molecules of Water (H 2 O ) Plus Sunlight and Chlorophyll Yields (arrow is read Yields)
6O 2 + C 6 H 12 O 6 6 Oxygen molecules (O 2 ) Plus One molecule of Sugar (C 6 H 12 O 6 )
Sugar stores the energy from the sun until it is broken down and the energy is released. The energy is in the chemical bonds that hold the sugar molecule together. When those bonds are broken, the energy is released. The process of breaking down sugar is called Cellular respiration. STOP
Producer Consumer Decomposer
Objective: Compare/contrast food/energy requirements of different organisms: compare food requirements in autotrophs and heterotrophs: illustrate food and energy requirements in autotrophs and heterotrophs: Describe the role of producers, consumers and decomposers in a food web.
Define …. -most (make food) through photosynthesis (photoautotrophs) -some through other chemical reactions. (chemoautotrophs) -source of all food in the ecosystem
Plants Bacteria Protists
What are we? Consumer (synonym) Heterotroph = an organism that cannot make its own food. -depends on producers for food and energy. Heterotrophs are consumers (define)
Classified by what they eat Herbivores Carnivores Omnivores Detritivores (eat dead things) ◦ scavengers and decomposers
Define herba = grass or herb vorare = to eat ex: caterpillars, deer, cattle
Define carnis= flesh ex: Lions, spiders, snakes
Define Ex: catfish, vultures, lobsters, crabs, shrimp (all bottom feeders), Earthworms (sometimes called a decomposer)
Define Omni = all ex: humans, crows, goats
Define Returns important nutrients to the environment Exs: bacteria, fungi, (worms)
Decomposers and scavengers are essential for the recycling of molecules in the ecosystem. Without them, the wastes and dead animals would just pile up and the nutrients would not be able to be used by any other organisms. They are nature’s recyclers.
Worms and insects are sometimes called decomposer and sometimes called scavengers. Anything that eats detritus (something dead) is a detritivore.
Objective: Explain the food web/food chain cycles in nature that affect living things.
How do scientists show the flow of energy? The movement of energy through an ecosystem can be shown in diagrams called food chains and food webs.
Define shows one possible path for the flow of energy. -arrows follow the flow of energy
Sunlight Producer 1 st level consumer (primary) 2 nd level consumer (secondary) 3 rd level consumer (tertiary) decomposer (energy flow stops here)
** What is missing? *Where does the energy come from? *What is the producer? *What is the 1 st level consumer? *What is the 2 nd level consumer? *What is the 3 rd level consumer?
Define -more realistic flow of energy -energy has many paths through many different organisms -each organism can have more than one role.
Producers Third-level/Tertiary Consumers Second-level /Secondary Consumers First-level /Primary Consumers
1) producers 2) primary consumers 3) secondary consumers 4) Herbivores 5) Carnivores 6) Ominvores 7) What is missing?
Aka Capstone Species = a species that if removed from the food web will cause the food web to collapse and most things to die off.
* Organisms use energy to move, grow, reproduce and carry out other life activities (90%) or lost as heat, so only a small amount (10%) of the energy is passed to the next level in the food chain.
* Most food webs only have 3 to 4 levels since there is not enough energy to support many feeding levels. Ocean food webs tend to have more levels.
Define -most energy at producer level amount of energy in the producer level limits the number of consumers the ecosystem can support. Therefore fewer producers =fewer consumers
an average of only 10% of the energy eaten by one level is passed onto the other levels. actual amounts varies depending on ◦ the type of ecosystem or biome ◦ and the amount of organisms living in the ecosystem or biome.