FLOW of MATTER and ENERGY EOC Lesson 11: Energy flow through an ecosystem

Where does most of the original energy come from?

ProducersConsumersDecomposers Use absorbed light to make their own food through photosynthesis An organism that obtains its food by eating other organisms Classified based on their food source Primary and secondary consumers Gets energy by breaking down the remains of dead organisms Return chemicals to environment Plants, green algae, and some bacteria All animals, many protists, some bacteria Fungi, many types of bacteria

Trophic levels and food chain Trophic level = each feeding level Food chain is used to show the energy flow from one organism to the next

Food web Food chain has only 1 path for the flow of energy. Food webs are used to represent several food chains because there are more than one producer and decomposer.

HerbivoresCarnivoresOmnivores Feed on or almost entirely on plants Feed on or mainly on animals Eats both plants and animals

Energy Pyramid Shows the energy loss between the trophic levels in an ecosystem Only about 10% of the energy is passed from one trophic level to the next Rest is “lost” to the environment as heat

Lesson 12: aerobic and anaerobic respiration

Chemical energy Stored in carbohydrates and other organic compounds Used for cellular activity Released through the process of respiration Mitochondria is the organelle that releases the energy This energy is stored in a compound = ATP (adenosine triphosphate)

ATP – nucleotide and 2 phosphate groups. Loses a phosphate to release energy and becomes ADP.

Aerobic vs. anaerobic Aerobic Requires oxygen cellular respiration Produces a lot of energy Anaerobic Does not require oxygen Fermentation Produces a little energy

Cellular respiration Takes place in the mitochondria C 6 H 12 O 6 + 6O 2  6 CO H energy GlycolysisKrebs Cycle (if oxygen is present) Electron transport chain Splits glucose molecule into pyruvic acid cytoplasm Produces 2 ATP Occurs in both aerobic and anaerobic respiration Also known as citric acid cycle Takes place in mitochondria Breaks down pyruvic acid into carbon dioxide and ATP High energy electrons from Krebs cycle to convert ADP to ATP Takes place in mitochondria Together produce 36 ATP molecules = total of 38 ATP

Lactic Acid FermentationAlcoholic Fermentation Converts pyruvic acid into lactic acid Yogurt and cheese Muscles during strenuous excerise Convert pyruvic acid into ethyl alcohol Wine, beer, bread Both processes are anaerobic respiration

Lesson 13: Photosynthesis and Cellular Respiration

Photosynthesis RAW materials: carbon, hydrogen, oxygen Use sunlight for energy Carbon dioxide + water +  glucose + oxygen Takes place in the chloroplast

Lesson 14: Biogeochemical Cycles

4 systems that make up earth Land Air Water And organisms These processes can be altered by human activities or by natural events

Biogeochemical cycles and Reservoirs Biogeochemical cycles Connection between livings things and Earth’s systems Involve the movements of organic and inorganic chemicals through the lithosphere, hydrosphere, atmosphere, and biosphere Reservoirs Places where various chemicals are stored and from which they flow and are recycled Carbon from rocks, as gas in atmosphere, and dissolved in water in tissues

4 main processes of the water cycle EvaporationTranspirationCondensationPrecipitation Water changing from liquid to a gas Movement of water from plants into the air from the openings in their leaves Water vapor turns to liquid Water that falls back to earth into bodies of water, land to be absorbed or flow off as runoff to resevoirs

Altered water cycle: impact on environment create dams which displace plants and animals which lived there, they can no longer reach their breeding grounds Irrigation Climate change: increase in global temperatures change the patterns of precipitation and evaporation

Nitrogen cycle – continuous movement of nitrogen through each of Earth’s systems 78% of Earth’s atmosphere Bacteria plays a critical role in the nitrogen cycle. Since most living things cannot use it directly, bacteria convert the nitrogen gas to ammonia and nitrates which can be used. Used to make proteins Overplanting of crops uses up the nitrogen in the soil, clear-cutting of forest expose soil to erosion carrying away nitrogen-rich soil, artificial fertilizers run off into nearby bodies of water causing an overgrowth of algae (algal blooms) which in turn uses up oxygen and kills off the organisms that lived in this ecosystem

Carbon-oxygen cycle: two cycles that are studied together between atmosphere and living things. Includes photosynthesis and cellular respiration Oxygen is used to burn fuel death and decomposition of living things forms fossil fuels which store large amounts of carbon Effects: combination of forest destruction and burning of fossil fuels increases the amount of carbon in the atmosphere. As a result, there is an increase in temperature all over the planet.