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.

http://whyfiles.org/coolimages/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…. 6CO2 + 6 H2O + sunlight

Six molecules of carbon dioxide (CO2 ) Plus Six molecules of Water (H2O ) Plus Sunlight and Chlorophyll Yields (arrow is read Yields)

6O2 + C6H12O6

6 Oxygen molecules (O2 )

Plus

One molecule of Sugar (C6H12O6 )

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

PlantsBacteriaProtists

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 1st level consumer (primary) 2nd level consumer (secondary) 3rd level consumer (tertiary) decomposer (energy flow stops here)

** What is missing?

*Where does the energy come from?

*What is the producer? *What is the 1st level

consumer? *What is the 2nd level

consumer? *What is the 3rd 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.