food and energy cycles cp biology - ecology. energy flow aaaan ecosystems energy budget is...
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Energy flowEnergy flow
An ecosystems energy budget is determined An ecosystems energy budget is determined by the amount of photosynthetic activity of the by the amount of photosynthetic activity of the producersproducers
Producers use light energy to synthesize Producers use light energy to synthesize organic molecules which are then used to organic molecules which are then used to make ATP in cellular respirationmake ATP in cellular respiration
Consumers obtain energy from organic Consumers obtain energy from organic molecules produced in lower trophic levelsmolecules produced in lower trophic levels
Consumers use food energy for:Consumers use food energy for: Cell respirationCell respiration Maintaining life processes (homeostasis, Maintaining life processes (homeostasis,
growth, development, etc)growth, development, etc) Some is lost in waste products and as heatSome is lost in waste products and as heat
Energy has to constantly be added to Energy has to constantly be added to and ecosystemand ecosystem
Organismal ecologyOrganismal ecology
Organisms can be put into 1 of 2 groups based on the Organisms can be put into 1 of 2 groups based on the costs and benefits of maintaining homeostasiscosts and benefits of maintaining homeostasis Regulators expend energy in response to changing Regulators expend energy in response to changing
environmental conditions; the energy costs cannot exceed the environmental conditions; the energy costs cannot exceed the benefits of regulating their internal environmentbenefits of regulating their internal environment
Conformers allow their internal conditions to vary with the Conformers allow their internal conditions to vary with the external environmentexternal environment
The principle of allocation says that organisms have a limited The principle of allocation says that organisms have a limited amount of energy to spend on all life functions; the energy amount of energy to spend on all life functions; the energy spent on one canspent on one can’’t be spent on the others.t be spent on the others.
The relationship between body temperature and ambient (environmental) The relationship between body temperature and ambient (environmental) temperature in an ectotherm and an endothermtemperature in an ectotherm and an endotherm
Primary productivityPrimary productivity
Gross primary productivity (GPP): The Gross primary productivity (GPP): The amount of light energy converted to amount of light energy converted to chemical energy by autotrophs in an chemical energy by autotrophs in an ecosystem; some is stored by plant, ecosystem; some is stored by plant, some is used for life processessome is used for life processes
Net primary productivity (NPP): the Net primary productivity (NPP): the amount of chemical energy available to amount of chemical energy available to consumers; also called biomassconsumers; also called biomass
Figure 54.3 Primary production of different ecosystemsFigure 54.3 Primary production of different ecosystems
Figure 54.4 Regional annual net primary production for EarthFigure 54.4 Regional annual net primary production for Earth
Secondary productivitySecondary productivity
Rate at which consumers convert the Rate at which consumers convert the chemical energy in the food they eat to chemical energy in the food they eat to their own biomasstheir own biomass Consumers use energy for life functions but Consumers use energy for life functions but
cannot completely digest the food so only cannot completely digest the food so only about 10% of the energy consumed is about 10% of the energy consumed is available to the next trophic levelavailable to the next trophic level
Pictured in a pyramidPictured in a pyramid
Figure 54.10 Energy partitioning within a link of the food chainFigure 54.10 Energy partitioning within a link of the food chain
Types of pyramidsTypes of pyramids
Pyramid of productivity (at trophic levels)Pyramid of productivity (at trophic levels) Biomass pyramidBiomass pyramid Pyramid of numbers (individuals)Pyramid of numbers (individuals) All are similar in that the bases are wide All are similar in that the bases are wide
(lots of producers) and narrow greatly at (lots of producers) and narrow greatly at the top (few top level consumers) and the top (few top level consumers) and only have 3-5 trophic levelsonly have 3-5 trophic levels
Biogeochemical cyclesBiogeochemical cycles
Global recycling: gaseous elements are Global recycling: gaseous elements are recycled in the atmosphere (oxygen, recycled in the atmosphere (oxygen, nitrogen, carbon, sulfur)nitrogen, carbon, sulfur)
Local recycling: elements that are solid Local recycling: elements that are solid are recycled in the soil (phosphorous, are recycled in the soil (phosphorous, potassium, calcium, trace elements)potassium, calcium, trace elements)
Matter is recycled, energy is notMatter is recycled, energy is not
U.S. map profiling pH averages for precipitation in 1999U.S. map profiling pH averages for precipitation in 1999