Science 10 ­ Notes ­ Organisms to Food Webs.notebook
February 09, 2015
Classifying Organisms
carnivore, producer, decomposer, omnivore, consumer, herbivore, earthworms, frog, grass, bacteria, algae, human, grasshopper, fungus organisms
(living things)
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Science 10 ­ Notes ­ Organisms to Food Webs.notebook
February 09, 2015
Food Chains
(Page 11)
A food chain is a step­by­step sequence linking organisms that feed on each other starting with a food source.
grasses ­> grasshopper ­> frog ­> heron
Detritus Food Chains
Detritus is waste from plants and animals, including their dead remains.
dead algae ­> tadpole ­> water boatman ­> yellow perch
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Science 10 ­ Notes ­ Organisms to Food Webs.notebook
February 09, 2015
Energy Movement in Ecosystems
The primary source of energy for most ecosystems is the sun. Photosynthesis is the process by which green plants (and others) use sunlight to produce carbohydrates (sugars).
Organisms can be classified according to their trophic levels (feeding levels) which depend upon how they gain their energy. 3
Science 10 ­ Notes ­ Organisms to Food Webs.notebook
February 09, 2015
Trophic Levels ­ Feeding Levels
first trophic level
second trophic level
third trophic level
fourth trophic level
fifth trophic level
primary producer
primary consumer
secondary consumer
tertiary
consumer
quaternary
consumer
autotroph
heterotroph
heterotroph
heterotroph
heterotroph
herbivore
carnivore
carnivore
top carnivore
one­way flow of energy grasses ­> grasshopper ­> frog ­> heron
primary
producer
primary consumer
secondary consumer
tertiary
consumer
As energy flows from organism to organism, energy is lost at each step. About 10% of the energy at one level is passed to the next level.
flower
ENERGY
1000 kJ
caterpillar
100 kJ
900 kJ LOST
bird
10 kJ
90 kJ LOST
Food chains rarely go beyond 5 trophic levels. 4
Science 10 ­ Notes ­ Organisms to Food Webs.notebook
February 09, 2015
Food Web
A network of many food chains is called a food web.
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