The Nature of Life on Earth (Chap. 5 - Bennett & Shostak)Overview of Chapter 5Slide 3Properties of Living SystemsSlide 5Properties of Living Systems: OrderProperties of Living Systems: ReproductionProperties of Living Systems: Growth and DevelopmentProperties of Living Systems: Energy UseSlide 10Metabolic “Class”Properties of Living Systems: Response to the EnvironmentProperties of Living Systems: Evolution and AdaptationProperties of Living Systems: Hierarchical OrganizationProperties of Living Systems: Regulatory CapacitySlide 16Properties of Living Systems: Diversity and SimilarityProperties of Living Systems: Medium for MetabolismProperties of Living Systems: InformationProperties of Living Systems: RecapiClicker QuestionSlide 22Slide 23Evolution as a Unifying ThemeStructural Features of Living SystemsStructural Features of Living SystemsBiochemical Features of Living SystemsBiochemical Features of Living SystemsBiochemical PathwaysMolecular Features of Living SystemsMolecular Features of Living Systems (continued)Instructional Features of Living Systems: Genetic CodeInstructional Features of Living Systems: Genetic Code (cont’d)Amino Acid CodonsSlide 35Slide 36Slide 37Slide 38Slide 39Slide 40Mutations and EvolutionSlide 42Slide 43Slide 44Slide 45EXTREMOPHILES NATURE’S ULTIMATE SURVIVORSWhat are Extremophiles?Types of ExtremophilesMore Types of ExtremophilesEnvironmental RequirementsSlide 51EXTREME PROKARYOTES HyperthermophilesMorphology of HyperthermophilesSample HyperthermophilesDeep Sea ExtremophilesExtremophiles of Hydrothermal VentsPsychrophilesSlide 58HalophilesBarophilesXerophilesSAMPLE PROKARYOTE EXTREMOPHILESDeinococcus radioduransChroococcidiopsisSlide 65Slide 66Slide 67Slide 68Other Prokaryotic ExtremophilesEXTREME EUKARYOTES THERMOPHILES/ACIDOPHILESEXTREME EUKARYOTES PSYCHROPHILESEXTREME EUKARYOTES ENDOLITHSEXTREME EUKARYOTES Parasites as extremophilesEXTREME VIRUSESPhylogenetic RelationshipsSlide 76Chronology of LifeWhat were the first organisms?Evolutionary TheoriesPace of EvolutionMat ConsortiaSlide 82Use of PsychrophilesUse of HalophilesUse of Alkaliphiles and AcidophilesTaq PolymeraseAlcohol DehydrogenaseBacteriorhodopsinBioremediationSlide 90Slide 91Life in Outer Space?Slide 93Slide 94CONCLUSIONSSlide 96Slide 97Slide 98Slide 991The Nature of Life on Earth(Chap. 5 - Bennett & Shostak)Notes for Chapter 526 & 28 September 2011HNRS 228Prof. Geller2Overview of Chapter 5Defining Life (5.1)Its properties, evolution and definitionCells: The basic units of life (5.2)Structure, composition, prokaryotes, eukaryotesMetabolism: The chemistry of life (5.3)Energy needs and sources; waterDNA and Heredity (5.4)Structure, replication, genetic code3Overview of Chapter 5Life at the Extremes (5.5)Extremophiles and their implicationsEvolution as Science (5.6)4Properties of Living SystemsNot lawsFrom Bennett & Shostak:Order (hierarchy)ReproductionGrowth and developmentEnergy useResponse to the environment (open systems)Evolution and adaptation5Properties of Living SystemsFrom Other SourcesHierarchical organization and emergent propertiesRegulatory capacity leading to homeostasisDiversity and similarityMedium for life: water (H2O) as a solventInformation Processing6Properties of Living Systems: OrderDefine “random”Define “order” in an abiotic systemWhy is “order” an important property”Examples of “order” in living systemsLevel of a biomoleculeLevel of the cellLevel of the organelleLevel of an ecosystemRelate to hierarchical7Properties of Living Systems: ReproductionDefine “reproduction” in abiotic termsE.g., fire, crystalsDefine “reproduction” in biotic termsWhy is it important property of living systems?Examples in living systemsMicrobes (fission)Cells (mitosis)Whole organisms Donkey8Properties of Living Systems: Growth and DevelopmentDefine “growth”Define “development”Why are “growth and development” important properties of living systemsExamples in living systemsOrganisms growOrganisms developExamples in abiotic systemsIce crystalsFire9Properties of Living Systems: Energy UseDefinitionsEnergy captureAutotrophs (photoautotrophs, chemoautotrophs)Heterotrophs (saprovores, carnivores, omnivores, etc.)Energy utilization (1st and 2nd Laws of Thermodynamics)Energy storageChemical bonds (covalent C-C bonds) and exothermic reactionsATP (adenosine triphosphate) and ADP (adenosine diphosphate)Energy dissipation (2nd Law of Thermodynamics)Why is “energy use” and important property of living systems?10Properties of Living Systems: Energy Use Catabolism BiosynthesisATPADP11Metabolic “Class”12Properties of Living Systems: Response to the EnvironmentDefine an “open” versus “closed” systemInteraction with the environmentStimulus followed by a responseWhy is “response to the environment” an important property?Examples in living systemsLeaf orientation to the sunEyesEars13Properties of Living Systems: Evolution and AdaptationDefine “evolution”Define “adaptation”Why is “evolution and adaptation” an important property in living systems?Examples of evolution in living systemsMacroscale: origin of species and taxaMicroscale: microbes resistant to antibioticsmoths resistant to air pollutionExamples of adaptationArticulation of the joints in animalsPlanar structure of leaves14Properties of Living Systems: Hierarchical OrganizationDefine “hierarchical organization”diagram of atoms to biomolecules to organelles to cells to tissues, etc.Define “emergent properties”Emergence of “novel and unanticipated” properties with each step of hierarchyExamples in living systemsHierarchyEmergent properties15Properties of Living Systems: Regulatory CapacityDefine “regulatory capacity”Relate to open systemsDefine “homeostasis”Role of feedbacks (positive and negative) and cyberneticsWhy is “regulatory capacity and homeostasis” and important property of living systems?ExamplesMolecular biology: gene regulationBiochemistry: enzymesOrganisms: temperatureGlobe: “Parable of the Daisyworld”16Properties of Living Systems: Regulatory CapacityStateVariableState VariableSensorSetPointPositive FeedbackNegative Feedback17Properties of