Week 2 Notes
Equilibrium in the Biosphere
Ecology
•
Study of the interactions between _____________ and their _________________ and
with each other.
Biosphere
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The part of the earth inhabited by organisms
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The Biosphere is broken into three basic structural zones
1) Lithosphere 2) Hydrosphere 3) Atmosphere -
Living vs. Non-living
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There are two factors which make up the biosphere.
–
–
_____________________
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Living components of the biosphere
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plants and animals…
_____________________
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Non-living components of the biosphere
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minerals, water, weather...
Week 2 Notes
Interactions within the Biosphere
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Abiotic vs Biotic
-When a non-living factor affects a living factor.
-i.e. The weather affecting a living organism
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Biotic vs. Biotic
– When a living factor affects another living factor.
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i.e. Two organisms fighting for the same food.
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Biotic vs. Abiotic
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Abiotic vs. Abiotic
Levels of organization
Week 2 Notes
Important Definitions
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Population: _______________________________________________________
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Community: ______________________________________________________
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Ecosystem: _______________________________________________________
–
•
________________
Biome: __________________________________________________________
–
_____________________________
General Terms
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Autotroph: _______________________
•
________________________________
•
–
________ ________ used to make organic compounds (glucose)
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Done by chloroplast containing organisms (plants, algae)
________________________________
–
Energy released by ____________ ___________ to make a sugar
•
–
•
Oxidizing hydrogen sulfide or methane
Done by bacteria in extreme environments (deep sea vents, hot springs)
Heterotroph: _______________________
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A _____________ consumer eats a producer
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A _____________ consumer eats a primary consumer
–
A _____________ consumer eats a secondary consumer…
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___________________ An organism that only eats plants. Ex) Rabbit, squirrel
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___________________ An organism that only eats animals.
Ex) Wolf, Lion, Tyrannosaurus Rex
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___________________ An organism that eats both plants and animals. Ex) Bear, Human
Week 2 Notes
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Scavenger -An organism that feeds on dead organisms or the wastes of organisms. Ex)
Vulture, Seagull,
•
Decomposer - An organism that breaks down organic wastes and the remains of dead
organisms into simpler compounds such as:
-carbon dioxide
-ammonia
-Water
Food Chain
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a linear illustration that represents the step sequence of who eats whom in the
biosphere.
–
used to show:
•
•
__________________________
Two types:
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Grazer: plant, herbivore, carnivore
Week 2 Notes
–
•
Detritus: organic waste, scavengers, decomposers
Characteristics:
 Energy is transferred from organism to organism
 Each time energy is transferred ____% is lost as heat or used for life processes
o Lost as heat during cellular respiration, stored in an unusable form,
metabolized by the organism itself for ATP to live
Trophic Levels
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_________________: how far an organism is from the original energy source
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Plants – _________________________
•
•
Original energy is from the sun
When an organism is ingested by another, energy is transferred
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Plant – mouse – owl
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Producer – primary consumer – secondary consumer (top carnivore)
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Trophic level 1, Trophic level 2, Trophic level 3
Food Webs
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In reality, a consumer relies on more than one food source
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If one source is scarce, consumer can eat more of something else
Week 2 Notes
•
Food web:
–
__________________________________________________.
–
more accurately represents energy pathways
•
Practice Questions
Pg 10 # 1,2,6
Pg 27 #4,5,6
who eats whom… really
Week 2 Notes
Laws of Thermodynamics
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Biosphere requires a constant ____________ of ____________
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Energy flows _____ _____ through the biosphere following basic scientific principles
called the laws of thermodynamics
First Law of Thermodynamics
______________________________________________________________________________
____________________________________________
(Law of conservation of energy)
__________________ = __________________
Ex) input  chemical energy of food = output  chemical energy & Heat
Second Law of Thermodynamics
______________________________________________________________________________
____________________________________________
______________  _________________ + _______________
Energy Flow
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About ____% of the energy is transferred from one trophic level to the next.
Week 2 Notes
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During any change, some of the energy is lost as ________________ or heat.
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Applied to an ecosystem, as energy flows through the community there is energy loss at
_________________________.
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Much of this loss is in the form of ___________ which is lost when food molecules are
broken down in the cells.
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There would be less energy loss in the community if consumers only fed on producers
Energy Flow in the Ecosystem
Ecological Pyramids
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Ecological pyramids illustrate the _____________________________________
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Solar radiation transformed in plants
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Plants create chemical energy
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Plant eaten by consumer
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Energy lost at each transformation
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Higher trophic level = _____________________
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Number of trophic levels limited b/c of loss of energy
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In ecological pyramids,
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Base -_________________________________________
–
Next Level - ____________________________________
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Higher Levels - __________________________________
Three types:
–
Numbers: _________________________________________
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Biomass: ___________________________________________
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shows how mass decreases as you move up the food chain
Week 2 Notes
–
Energy: ___________________________________________
Week 2 Notes
Practice Questions
Pg 34 #2,3,4,6,8
Human Interference in the Ecosystem
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Pesticides – Used to kill pests, however they get eaten and the toxin accumulates in the
food chain. Causes a loss in diversity.
•
•
Example: DDT: dichloro diphenyl trichloroethane
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developed as a biological weapon in WWII
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1950’s - used as a pesticide for insects
DDT also affects human populations
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found in breast milk
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came from sprayed crops
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animals that ate crops
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Banned in Canada and US in 1970’s
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Not banned in other areas - Mexico, Central America
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Continues to be produced as a cheap pesticide in poorer nations
Biological amplification
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______________________________ at the top level of the pyramid
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toxins accumulate in fatty tissue
-not released in wastes
•
magnifies each time you move up
•
higher trophic level - higher
concentration
Week 2 Notes
In preparation for your summative assessment on this section, complete the
following questions in your textbook. (Answers available upon request)
Pg 18 #1,2,3,5,8
Pg 38 #1,2,3,5,6,7,8,9,10
Send me your answers to questions 6-10 on pg 38, as well as any questions you
have about the information before you do your summative assessment for this
week.