3EcologyThe branch of biology that deals with the interactions between organisms and the relationship between organisms and the environment.
4Do Now:Draw a flow chart to represent the organizational relationships between the following terms from the most inclusive to the least inclusive: ecosystem, population, species, community, and biosphere.
6Levels of Organization Ecosystem OrganizationSpeciesPopulationCommunityEcosystemLandscapeBiosphereCellular OrganizationCellsTissuesOrgansOrgan SystemsOrganismsSPECIES
7Homo sapiens with Homo sapiens SpeciesA group of organisms capable of producing more members of the same organism..Homo sapiens with Homo sapiensNot Homo sapiens with Homo habilus
8The Brown Trout Salmo trutta SpeciesThe Brown Trout Salmo trutta
9Includes all the members of a species found in a given area. PopulationIncludes all the members of a species found in a given area.Ex: sunfish in a pond
10Community Includes all the populations in a given area. Ex: all plants, animals, and microorganisms make up a pond community
11Interaction of biotic and abiotic factors EcosystemIncludes all the members of the community plus the physical environment in which they live in.Interaction of biotic and abiotic factors
12Abiotic Factors Nonliving factors. The abiotic factors of an ecosystem include the physical and chemical factors that affect the capacity of an organism to live and reproduce. These factors are:1. Intensity and duration of light2. Temperature range3. Amount of moisture4. Type of substrate5. Availability of inorganic substances and gases6. pH
13Biotic Factors Living factors These factors directly or indirectly affect the environment.Thus, the organisms, their presence, parts, interaction, and wastes all act as biotic factors.These interactions include:1. Nutritional relationships2. Symbiotic relationships
14Requirements for a Stable Ecosystem The ecosystem involves interactions between living and nonliving things. Certain requirements must be met for a stable ecosystem to exist:There must be a constant supply of energy (sunlight for photosynthesis).There must be living organisms that can incorporate the energy into organic compounds (food).There must be a recycling of materials between organisms and the environment.
15Limiting FactorsDetermines the types of organisms which may exist in that environment.Examples are:A low temperature common to northern latitudes determines in part what species of plants can exist in that area.The amount of oxygen dissolved in a body of water will help determine which species of fish will exist there.
16LandscapeA spatially heterogeneous region that includes several interacting ecosystemsConnections among ecosystems found in a particular area.
17The portion of the earth in which life exists. BiosphereThe portion of the earth in which life exists.The biosphere is composed of many complex ecosystems that include water, soil, and air.
18Ecological Organization Population ( or )Community ( )Ecosystem ( )Biosphere ( )
19Do Now:Compare and contrast potential energy and kinetic energy using biological or ecological examples and references
20Types of energy Energy: the capacity or ability to do work. Potential Energy: Stored energy.Kinetic Energy: The energy of motion.
21Do Now:Define energy and briefly describe how the different forms contribute to the continual energy needs of organisms
22Types of energyHeat Energy: thermal energy that flows from an object with a high temp. (heat source) to an object with a lower temp. (heat sink).
23Nuclear Energy: energy found within atomic nuclei.
24Types of EnergyElectrical Energy: energy that flows as charged particles.
25Thermodynamics: The study of energy & its transformations. 1st Law of Thermodynamics: energy cannot be created nor destroyed, but it can be transformed.2nd Law of Thermodynamics: when energy is converted some usable energy is degraded into a less usable form. (Entropy)
26Do Now:Cellular respiration occurs in both plant and animal cells while photosynthesis only occur in plant cells. How are plant and animals connected via these two processes? Be sure to include balanced chemical equations as part of your answer.
27Closed and Open Systems Earth is an open system because it receives energy from the sun.
28Types of Energy Chemical Energy Potential Energy Mechanical (Kinetic) EnergyRadiant (Solar)Nuclear EnergyHeat EnergyElectrical Energy
29Energy Flow Relationships For an ecosystem to be self-sustaining, there must be a flow of energy between organisms.The pathway of energy flow through the living components of an ecosystem are represented by food chains and food webs.
30Nutritional Relationships Involves the transfer of nutrients from one organism to another within an ecosystem.In terms of nutrition, organisms are either autotrophs or heterotrophsSEE OWL LAB
32Energy Losses The mouse receives energy from the food it eats. Cells extract the food's energy for growth, acquiring food, escaping enemies lost as heat. Some lost in the mouse's waste (feces).The remaining energy is stored in the mouse's body and is available to the organism that preys on it.About 90% of the energy is used or lost, only 10% is available to predators.
34Biological Magnification A nondegradable or slowly degradable substanceThat becomes more and more concentrated in the tissues of organisms at higher trophic levels of a food web.* Dichloro-Diphenyl-Trichloroethane (DDT)* Polychlorinated biphenyls (PCBs)
37PCBs in Food WebsPCB concentrations in animal tissue can be magnified up to 25 million times.Microscopic organisms pick up chemicals from sedimentsConsumed in large numbers by filter feeding zooplankton.Mysid shrimp then consume zooplanktonfish eat the mysidand so on up the food web to the herring gull.(Figure and caption from Our Stolen Future, p. 27)
38DDT DetectionIn 1962, Rachel Carson, a former U.S. Fish and Wildlife Service (USFWS) scientist and writer, published Silent Spring, outlining the dangers of DDTFig. 41-8, p.736
39Do Now:Discuss the contributions of saprotrophs and detritivores to a balanced ecosystem.Identify two representatives of each group in your discussion
40(A) Food ChainsGreen plants and other photosynthetic organisms are the organisms in an ecosystem that can convert radiant energy from sunlight into food.A food chain involves the transfer of energy from green plants through a series of organisms with repeated stages of eating and being eaten.
42(B) Food WebsIn a natural community, most organisms eat more than one species and may be eaten, in turn, by more than one species.Thus, the various food chains in a community are interconnected forming a food web.SEE OWL LAB
43Food Web at the Edge of an Eastern Deciduous Forest
44Do Now:Define and discuss three applications of the term: ecological pyramid.What accounts for the shape of the pyramid?Use sketches of each type of pyramid with associated quantitative units to support your comparison.
45(C) Pyramid of EnergyThe greatest amount of energy in a community is present in the organisms that make up the producer level.Only a small portion of this energy (10%) is passed on to primary consumers, and only a smaller portion (10% of the original 10%) is passed on to secondary consumers.A pyramid of energy can be used to illustrate the loss of usable energy at each feeding level.
48B. ALL living organisms must carry out ALL 8 life functions NutritionSynthesisTransportGrowthRespirationRegulationReproductionExcretion
49An organism capable of making their own food AutotrophAn organism capable of making their own foodPhotosyntheticChemosynthetic
50Chemosynthesis A type of autotrophic nutrition Does not require light as an energy sourceEnergy is obtained by chemical reactions within the cellExample: Hydrothermal vent bacteria
51Photosynthesis The most common type of autotrophic nutrition In this process, organisms use energy from sunlight, carbon dioxide, and water to make food (usually glucose)
52Chloroplast Contains pigments called: chlorophylls (a & b greens)Xanthophylls (yellow)Carotenes (orange)It is in the chloroplast that light energy is trapped by chlorophylls and glucose is formed as the product. (food)
54Wavelengths effects on Photosynthesis Absorption of Light byChlorophyll a and Chlorophyll bWhich Wavelengths are the best for photosynthetic plants?Which Wavelength is the worst?Chlorophyll bChlorophyll aVBGYOR
55ROY G BIVThe maximum amount of photosynthesis will occur when exposed to red and blue light because it is these two colors that are easily absorbed in great quantity by the chlorophyllFor green leaves, green light is reflected and therefore has the least affect on photosynthesis
56Formula for Photosynthesis 6CO2 + 12H2O + radiant energy C6H12O6 + 6H2O + 6O2Formula for Cellular RespirationC6H12O6 + 6O2 + 6H2O 6CO2 + 12H2O + work energy
58Photosynthesis occurs in two stages: Light ReactionDark Reaction
59Structure of Chloroplast Light reactionsDark reactions
60Photosynthesis: An Overview Section 8-36CO2 + 12H2O + radiant energy C6H12O6 + 6H2O + 6O2SunlightwaterO2SugarsCO2ChloroplastNADP+ADP + PLight-DependentReactionsCalvinCycleATPNADPH
611. Light Reaction Occurs in the grana of the chloroplast. First stage of photosynthesis.Begins with the absorption of light energy by chlorophyll.Photolysis occurs- a reaction in which H2O molecules split into oxygen and hydrogen.All oxygen given off during photosynthesis comes from the photolysis of water.ATP (Adenosine triphosphate), which is a form of chemical energy, is produced.
62Light Reaction Oxygen (6O2) Chloroplast (H2O) AKA Photolysis NADPH I am out of here!12 WATER molecules(H2O)12 Hydrogen12 HydrogenAKAPhotolysisNADPH+ ATP(This all occursIn the Grana.)
63Dark Reaction (This all occurs in the Stroma.) NADPH +ATP 6(CO2) “Calvin Cycle”“LightIndependentReaction”(This all occurs in the Stroma.)NADPH+ATP12 Hydrogen12 HydrogenCarbon Fixation6(CO2)C6H12066(H20)AKAGlucose
662. Dark Reaction Occurs in the stroma of the chloroplast. The second stage of photosynthesis.It is here that CO2 is converted to carbohydrates by a process called carbon fixation.CO2 PGAL C6H12O6Light is not required.The dark reaction requires ATP from the light reaction for it to take place.
67Factors Affecting the Rate of Photosynthesis Light IntensityWaterCarbon dioxide levelTemperature
68Adaptations for Photosynthesis A. Unicellular Organisms1. Almost all chlorophyll-containing unicellular organisms are aquatic. (live in water)2. The raw materials for photosynthesis are absorbed directly from the water and into the cellEx: algae &cyanobacteria
69Adaptations for Photosynthesis B. Terrestrial Plants (land-dwelling)1. Occurs in leaves that provide the maximum surface area for the absorption of light.
70Plants Leaves- have stomates for gas exchange Stems- have lenticels for gas exchangeRoots- gas exchange occurs across a moist membraneof root hairs (diffusion)
71Do Now:Briefly explain the process of cellular respiration and uses of the energy obtained from the process. Your answer should include the following terms: glucose, water, carbon dioxide, chemical energy, and oxygen. What organisms carry on this process?
73Glycolysis (splitting glucose) Net Energy Yield from GlycolysisEnergy requiring steps:2 ATP investedEnergy releasing steps:2 NADH formed4 ATP formedNet yield is 2 ATP and 2 NADH
74Glycolysis (splitting glucose) All three reactions with GlycolysisGlycolysis occurs in cytoplasmReactions are catalyzed by enzymesGlucose 2 Pyruvate(six carbons) (three carbons)
75Equations for Anaerobic Respiration 1. Lactic Acid Fermentationglucose 2 lactic acids + 2 ATP’s2. Alcoholic Fermentationglucose 2 alcohol + 2 CO2 + 2 ATP’sIn each equation, enzymes are used and a net gain of 2 ATP’s are producedAerobic RespirationGlucose + O2 H2O + CO ATP’sAgain, enzymes are used and a net of 36 ATP’s are produced
76Equations for Anaerobic Respiration glucose 2 lactic acids + 2 ATP’sglucose 2 alcohol + 2 CO2 + 2 ATP’sIn each equation, enzymes are used and a net gain of 2 ATP’s are produced
77Equation for Aerobic Respiration glucose + O2 H2O + CO ATP’sAgain, enzymes are used and a net of 36 ATP’s are produced
79Do Now:What is the human impact on net primary productivity? What are the potential environmental problems associated with this impact and what changes would be required to minimize human impact?
80Net Primary Productivity (NPP) = Gross Primary Productivity (GPP) (total energy from photosynthesis /unit area/time) - Plant respiration (energy invested by plants)
81(NPP) = GPP (rate) – Plant Respiration Total energy producedEnergy costHumans compete with other speciesfor energy.Our planet cannot handlethe burden from human overpopulation.
82Humans compete with other species for energy. Our planet cannot handle Table 9l-1: Average annual Net Primary Productivity of the Earth's major biomes. Ecosystem Type Net Primary Productivity(kilocalories/meter 2 /year) Tropical Rain Forest 9000 Estuary Swamps and Marshes Savanna 3000 Deciduous Temperate Forest 6000 Boreal Forest 3500 Temperate Grassland 2000 Polar Tundra 600 Desert < 200Humans compete with other speciesfor energy. Our planet cannot handlehuman overpopulation.
83There are 3 basic organisms in a food web: 1)Producers2)Consumers2a) Primary consumers2b)Secondary consumers3)Decomposers
85There are 3 basic organisms in a food web: Producers- include green plants and other photosynthetic organisms that synthesize the organic nutrients that supply energy to other members in the community.
86Question Briefly discuss the role of autotrophs in an ecosystem
87There are 3 basic organisms in a food web: Consumers- include all heterotrophic organisms. Organisms that feed on green plants are primary consumers, or herbivores. Secondary consumers, or carnivores, feed on other consumers. Omnivores eat producers and consumers.
88There are three basic classes of organisms in a food web: Decomposers – are the organisms (saprotrophs) that break down wastes and dead organisms so that chemical materials are returned to the environment for use by other living organisms.
91Do Now:What are krill? Using appropriate terminology, discuss the role of krill in the Antarctic food web, and describe what has been happening to the population of these animals over that past 150 years and why. What has been the impact on this Antarctic ecosystem of human related change in the global environment?
92Do Now:Today, commercial fishermen are “fishing down the food web.” This is unsustainable. WHY? How can this movement down the marine food web be reversed?