How do organisms obtain nutrients?Although energy moves throughecosystems in a one-way direction,nutrients are recycled.Three basic nutrient cycles arepresent in all ecosystems allowingorganisms to obtain needednutrients to function effectively.
Water CycleDriving force is the sun.Consists of the alternation betweenevaporation and condensation.Most water returned to theatmosphere comes from evaporationfrom the oceans.
Water Cycle TerminologyWater vapor- gaseous form of water inatmosphereEvaporation- liquid water from bodies ofwater becomes gas returned toatmosphere.Transpiration- loss of water by land plantsCondensation- process which watermolecules gather in atmosphere “changefrom gas to liquid” when cooled.Precipitation- water falls from atmosphereto ground (rain, snow, sleet, or hail)
Why is the water cycle important?Water is the most importantnonliving (abiotic) component of anecosystem.Water essentially determines whatorganisms we find in an ecosystem.What is the major differencebetween the tropical rainforest andthe desert? Why?
Carbon CycleCarbon cycles between the livingorganisms and the non-livingcomponents of ecosystem.Carbon exists in the atmosphere ascarbon dioxide (CO2)Why do living things need carbon?
Carbon Cycle TerminologyPhotosynthesis- process where sunlight,CO2 and H2O is used to make foodRespiration- process by which animalstake in O2 given off by plants and give offCO2***THE OPPOSITE OFPHOTOSYNTHESIS!Fossil fuels- formed by pressure appliedto dead organisms that are buried insediment. They are carbon and releaseCO2 when burned.Combustion- burning of fossil fuels
Why is the carbon cycle important?Energy for living organisms(carbohydrates).***Humans in the United States arealtering this cycle.Burning of too many fossil fuels isreleasing extra CO2 into theatmosphere creating “globalwarming” due to increasedgreenhouse effect.
Nitrogen CycleThe atmosphere contains 80%nitrogen gas (N2).However, this nitrogen can not beused by most living things.Bacteria are the only organisms thatare use nitrogen directly from theenvironment.They can fix nitrogen for plants touse
Nitrogen Cycle TerminologyNitrogen fixation- nitrogen gas inatmosphere to ammonia (bacteria insoil, lightning)Nitrification- ammonia to nitrate(bacteria in soil)Assimilation- absorption of ammoniaand nitrate by plantsAmmonification- break down of deadorganisms returns nitrogen to soil(bacteria and fungi) as ammonia.Denitrification- conversion ofammonia back to nitrogen gas(decomposers).
Why is the nitrogen cycle important?Why is nitrogen important toliving things?How do plants obtain nitrogen?Why are bacteria SO importantto the nitrogen cycle?How do we obtain nitrogen?