Mrs. Saullo



Chapter 2: Environmental SystemsModule 4: Systems and MatterA Lake of Salt Water, Dust Storms, and Endangered SpeciesThe story of Mono Lake shows how a change in one factor can have unexpected effects.Background of Mono LakeCharacterized by towers of limestone called tufa (created by evaporation of water)terminal lake…no outputSo salty that fish cannot survive…only brine shrimp ad alkali fly larvaeUsed as a migration stop for birdsStarting in 1941 the lakes health was deteriorating due to water diversion of feeder streams....Can cause dust stormsMay contain high amounts of arsenicDestroys ecosystem (algae, brine shrimp), harms migratory birdsThe health of Mono Lake is recovering due to decreased water diversion from feeder streams. To offset the human need of water…L.A. needed to reduce water consumptionUsed xeriscaping (native plants not requiring water rather than grass-covered lawns)Required low flow shower heads and water-saving toiletsMatter and AtomsMatter is anything that has mass and occupies space.Basic Unit is the Atom (made of protons, neutrons and electrons).30219658509000-635-127000An Element is a substance made of one type of atom.Found on the periodic table26365209096600Atoms vs. Ions vs. IsotopesAtomsIonsIsotopesAll represent specific ElementsSame number of protons….atomic numberMost common isotopeElectrically neutralStableGain or lose electrons to get full outer energy levelVarying mass numbers RadioactivityRadioactive isotopes like U-235 undergo radioactive decay as their unstable nuclei come apart emitting energyHalf-life: time it takes for ? of the original radioactive “parent” element to decayUseful….carbon datingChemical BondsIonicPolar covalentNonpolar covalentHydrogenMetal and NonmetalExchange electrons to form ionsSaltShare electrons unequallySugar, WaterShare electrons equallyOil, FatsWeak bondElectrical attraction between two polar molecules7795386663300Water PropertiesUnique properties of water make life on Earth possible…Facilitate transfer of chemical elements and compounds from one system to anotherSupport conditions necessary for life Due to the polarity of water….Universal solvent: dissolves solutes with the same polarity (polar or ionic)Surface tension: due to the cohesion of water; water making hydrogen bonds with other water molecules; “skin” on top of waterCapillary action: water moving up a hollow tube; requires water to be adhesive to “tube”High boiling point: allows water to be a solid, liquid and gas in Earth’s temp. rangeHigh specific heat: it takes a lot of energy to change water’s temperatureWater floats as a solid due to its crystalline structure making the molecules expand as it freezes.Acids and BasesAll acids and bases are aqueous (water-based) solutions pH scale shows relative strength of acids and bases.Logarithmic….based on the power of 10pH of 3 is 10x more acidic then a pH of 40-14Acids….below 7Neutral…7Bases…above 7AcidsBasesDissociates into Hydronium or hydrogen ions (when dissolved in water)Start with H-HCl, H2SO4Dissociates into Hydroxide ions (when dissolved in water)Ends with –OH or –HNaOH, NH3Chemical ReactionsConservation of Matter….matter cannot be created or destroyedBalancing ReactionsExample: Combustion of Propane (C3H8)95095514634400Can occur in one or both directions….OzoneCombustion releases metals/sulfur associated to fossil fuels into the atmosphere…they deposit somewhere else…no longer tied up in the fossil fuel MacromoleculesOrganic vs. InorganicOrganicInorganicContains carbon along with hydrogenFossil fuels Carbs, lipids, proteins, nucleic acidsDoes not contain carbon to carbon bonds…does not have carbon along with hydrogenSalt (NaCl)CO2, H2OMacromoleculesCarbohydratesLipidsProteinsNucleic AcidsMonosaccharides like glucoseSugarCellulose (cell walls)StarchSaturated vs. Unsaturated FatsFatty acidsWaxSteroidsCholesterolTriglyceridePhospholipids (cell membranes)Amino acidsEnzymesPeptide bondsMuscleantibodiesNucleotidesDNARNACode of lifeCellsSmallest structural and functional component of organisms.Made of Carbohydrates, proteins, lipids, nucleic acids and aqueous solutions surrounded by a membrane.Module 4 OUTPUT….A Lake of Salt Water, Dust Storms, and Endangered SpeciesCompare and contrast Mono Lake to the Aral Sea…use a Venn Diagram. Matter and AtomsComplete the Table below. Pg.34Element Name and SymbolAtomic NumberMass NumberCommon substance that contains the elementCarbon (C)Hydrogen (H)Oxygen (O)Nitrogen (N)Phosphorus (P)Sulfur (S)Draw an atom of CarbonWatch the video “How Does Radiocarbon Dating Work?” on Youtube and write notes on how carbon dating works as well as how it is useful in science. Feel free to watch additional videos.Chemical BondsCreate cartoons that show differences between different types of chemical bonds.Water PropertiesMini-Lab….For each demo, name the property of water exhibited.Pour water into a glass until it forms a slight dome on top. Carefully rest a paperclip on the surface.Drop ice into a clear bottle of water and seal the top. Then turn the bottle upside down until the ice rises to the water’s surface.Drop a couple of drops of dark food coloring into a beaker of water. Watch as the color dissolves in the water. Dip the edge of a paper towel into the beaker of water in which the food coloring has been added. Lay the rest of the paper on the table and watch as the water creeps up the plete the table below….Property of WaterFunction in environmentSurface tensionCapillary actionHigh boiling and melting pointsExpands when freezesGood solventAcids and BasesMini-labDraw the pH scale. Label the portion that represents acids, neutral, bases. Also label H+ and OH-Complete the following table….pHTap waterTap water after blowing into the water for 30 seconds using a strawUse the data above to infer why is the pH of rain slightly acidic? Create a picture to help you remember this fact.Place a piece of chalk (made of Calcium carbonate…similar to limestone and shell fish) in vinegar. Create a visual to display what you observe. How did pH change? What reaction are you observing? How does this relate to environmental science?Using Fig.4.7 (pg.39) and the figure below, answer the following questions:At what pH range can all selected species survive? Is this acidic, neutral or basic?At what pH range do the fewest species survive? Is this acidic, neutral or basic?Which species are the most sensitive to acidic environments? How can you tell?Which species are the most tolerant of acidic environments? How can you tell?Do you think pH is an important factor in determining the health of an ecosystem? Why or why not?Chemical ReactionsMini-labWhat happens to wood when it burns?What happens to organic matter when an animal decomposes?What is the source of plant matter as it grows?Balance the following reactions….MacromoleculesCreate a foldable or chart that illustrates differences between carbohydrates, lipids, proteins and nucleic acids. Be sure to include pictures, monomers, examples, important functions.CellsDraw an animal cell and a plant cell; label at least 5 parts/organelles in each drawing.Module 5: Energy, Flows and FeedbacksINPUT….Energy What is the difference between energy and power?Energy is the ability to do work or cause changePower is the rate at which work is doneEnergy = power x time……kWh (kilowatt-hours) (seen in a power bill)Power = energy/time….kW (kilowatt) (tells the power of the turbine generating electricity)Basic unit of energy is called a joule (J)There are other units of energy….There is A LOT of math involved in energy in describing energy, work and power (that is why we are doing a lab) Do the Math (pg. 46)…..Let’s do it togetherForms of EnergyPotential vs. KineticPotential: stored energy that has not been released yetChemical energy: energy stored in the bonds of compoundsFood: fat has more energy than carbs.Fuels: biofuels vs. fossil fuelsNuclear energy: energy stored in the nuclei of elementsReleased as thermal energy (temp.=kinetic)Kinetic: energy of motion; often generated when potential energy is releasedTemperature: measure of the average kinetic energy of a substance (also called thermal energy)Mechanical: movingElectromagnetic energyCarried by photons Energy depends on wavelengthLong wavelength=low energyShort wavelength=high energyWavelengths in the visible light spectrum are used by plants for photosynthesis.Majority of the radiation produced by the sun lies within 250-2500 nm or 2.5 x 10-8 m - 2.5 x 10-6 mEnergy ConversionsEnergy cannot be created nor destroyed…therefore it is conserved.Energy is converted from one form to another….efficiency measures how “good” this conversion is…in other words… the more efficient the conversion the least amount of energy is lost as “waste” heat Think food chains or driving your car….chemical to mechanical (some lost as heat)The form and amount of energy in an environment determines what kinds of organisms can live there. LatitudeFurther away from equator = less energy from sun = less diversity of life Deep ocean vents lack sunlight….energy comes from chemicals (sulfur) emitted from vents…supports specialized forms of life (plant-less) that can respire anaerobicallyLaws of ThermodynamicsFirst Law of ThermodynamicsEnergy cannot be created nor destroyed but it can change from one form to anotherSecond Law of ThermodynamicsWhen energy is transformed, the amount of energy remains the same BUT its ability to do work diminishes.Energy efficiency: ratio of the amount of energy expended to the amount of energy introduced to the new system (in other words…energy input/energy output)Uh Oh….Math again….Calculate the overall energy efficiency of converting coal into compact fluorescent lighting, which is 20 percent efficient. How does this compare to the overall efficiency of an incandescent light bulb (pg.48)?Energy Quality: the ease at which an energy source can be used for workHigh (gasoline) vs. Low (wood)Entropy: disorder, randomness2nd law of thermodynamics also says that all systems move toward randomness rather than toward order unless an input of energy from outside the system creates order.System DynamicsWhy is it important to look at the whole system rather than only the pars of a system?Need to know how all the parts interactA system is defined by the nature of the interactions and its various components.Open vs. Closed systemOpenClosedMost systems are openMatter and energy are exchanged across bordersExample: a lake interacts with the surrounding land and atmosphereMatter and energy exchanges do not occur across boundariesExample: Biobottles, Underground caveInputs and OutputsInputs: matter and energy coming “IN” to the systemOutputs: matter and energy coming “OUT” of the systemSteady StateEquilibriumInputs=OutputsFeedbacks:PositiveNegativeBad for the systemAmplify the change in the systemExample: Polar ice melting, increasing the albedo effectKeeps the system at a steady stateExample: Reintroducing the wolves to Yellowstone…predator-prey relationshipsChange across space and timeTemperature, precipitation, soil composition, topography and altitude vary among natural systems….they determine the biologics that exist in that regionStudying natural variations helps scientists understand correlations between species distribution and landscape variation.Can be used to predict the effect of changes in a given ecosystemGive information so that humans can help conserve or mitigate the effects of our impactsModule 5 OUTPUT….EnergyWho’s Got the Power Lab Forms of EnergyDraw a picture to show difference between kinetic and potential energy.(Optional) Design a lab to test if biofuels or fossil fuels have more chemical energy. If time….Carry it out!!Energy ConversionsDescribe how energy from the sun is able to be used by organisms on Earth. Use a picture to aid in your description. Label the different forms of energy.Laws of Thermodynamics1st and 2nd law of thermodynamics: Create a drawing (not a car) that illustrates the fundamental concept that energy can neither be created nor destroyed but can change from one form to another. Be sure to show how efficient the system is.Energy Quality: List at least 3 other sources of energy other then gasoline or wood….which one do you think has the highest energy quality? Create a visual to aid in your answer.Entropy: create a visual to depict one of the examples of entropy on page 50System DynamicsCreate a pocket to keep 2 index cards…Label one Positive Feedback Loop and the second Negative Feedback Loop…Write examples on the back of the appropriate card ................
................

In order to avoid copyright disputes, this page is only a partial summary.

Google Online Preview   Download