Ecology Review

Gateway ReviewChemistryEcology ReviewEnergy Flowflow of energy through an ecosystem flow: Producers Consumers DecomposersFood Chains series of steps in which one organism transfers energy by eating and being eatenFood Web network of food chains in an ecosystem showing the complex interactions between organismsIn order to live, organisms must obtain energy and nutrientsHeterotrophs obtain energy and nutrients from the food they eatAutotrophs obtain energy from the sun/obtain nutrients from the soil

Law of Conservation of EnergyEnergy cannot be created or destroyed it can only change forms.Energy moving through food chain/webonly 10% available for next level uprest is used for energy to carry out life functions, increase body mass, and lost as heatProducersorganisms that make their own food use energy from the sun and carbon from the environmentbottom of the food chainprocess of making food = Photosynthesis6 CO2 + 6 H2O + light energy C6H12O6 + 6 O2requires carbon dioxide, water and energy (sunlight)makes sugars and gives off oxygen gas

Why are producers necessary in an ecosystem?PhotosynthesisProcess of using energy from the sun to produce sugars (glucose)6 CO2 + 6 H2O + light energy C6H12O6 + 6 O2Occurs in chloroplast of plants and some algae

Consumersorganisms that cannot make their own food obtain energy through eating other organismsHerbivore eats only plantsCarnivore eats only animalsOmnivore eats both plants and animalsseveral levels in food chains (food webs)primary eat only producerssecondary and higher eat other consumers that eat the producersdecomposers eat dead matter, recycle nutrients for producers to use againMeans of obtaining nutritionPredationEcological interaction in which one organism (predator feeds on another living organism (prey)Predator may or may not kill the preyScavengingAn animal ingests dead plants, animals, or both (vultures, termites, beetles)Decomposer (saprophytes)Break down (absorb nutrients from) nonliving organic material corpses, plants, waste of living organisms- and convert them to inorganic forms (bacteria, fungi)use cellular respiration to break down food into energy and nutrients6 O2 + C6H12O6 6 CO2 + 6 H2O + energyreverse reaction of photosynthesis

RespirationProcess of using energy from sugar (glucose) to produce ATPC6H12O6 + 6 O2 6 CO2 + 6 H2O + 38 ATPOccurs in mitochondriaOccurs in both animals and plantsATP provides energy to do work in the cellWhen ATP is used, it is converted to ADP; respiration then uses energy in sugars to convert ADP back to ATP by adding a phosphate

How are photosynthesis and respiration related?Food Web & Food Chains Review

1. List 3 food chains within the food web above.ABC

2. Using the three food chains just listed above, list the producers.3. Using the three food chains just listed above, list the first order consumers.4. Using the three food chains just listed above, list the carnivores.5. Using the three food chains just listed above, list the second order consumers.Carbon Cycle

Carbon: key ingredient in all living thingsProcesses involved:Biological (photosynthesis)Geochemical (release of CO2 by volcanoes)Human activity (burning of fossil fuels)Carbon Cycle

You take in carbon in the foods you eat return CO2 to the air when you exhaleA plant also returns CO2 to the air when it uses its own sugars as a source of energy another plant takes in CO2 during photosynthesis = complete cycle of carbon within a communityCarbon CycleHundreds of millions of years ago plant bodies buried before decomposers got to them they became sources of fuel (coal, oil, natural gas) today, fuels are burned and energy is released the carbon in the fuels is returned to the air as CO2

Carbon passed from one organism to another abiotic community back to the plants = carbon cycleThe Carbon (CO2) CycleCarbon enters food chains through photosynthesis. Plants in land ecosystems absorb carbon dioxide into their leaves from the air and use it to make organic matter, which accumulates as plant tissue (biomass). The carbon is then passed along food chains as organic matter. Carbon is released from food chains back into the atmosphere through cellular respiration Plants, animals and decomposers all release carbon dioxide, and the carbon cycle is complete.

Note: Carbon cycles at a fast rate. However, some carbon atoms get stored for millions of years as coal, oil and natural gas. Coal and oil are formed from partially decomposed fossil remains of organisms. Natural erosion, volcanic activity and fire eventually release carbon from these stores.