Lecture IX: Start of Life.Last LectureOutlineLectureEES 1040 1st Edition Lecture 8Lecture IX: Start of Life.Last LectureEvolutionOutlineI. 4 Ingredients for LifeII. Miller and Urey experiment 1953III. S.W. Fox 1969 on ,Uni of MiamiIV. VirusesV. Eckward Wimmer 2002, Suny Stony BrookVI. When did life begin?VII. Where did life start?VIII. Life starts between 4.0 BA and 3.8 BALectureI. 4 Ingredients for LifeA. Proteins1. Made of strings of simple organic molecules – amino acidsa. Building materialsb. Catalysts for chemical reactionB. Nucleic acids1. DNA2. RNAC. Organic phosphorus compounds1. Used to transform light or chemical energy into energy for metabolismD. Container1. Cell membrane2. Provides an isolated chemical systemII. Miller and Urey experiment 1953A. Life?1. Self-organizing2. Self-regulating3. Self-replicatinga. Proteins – made form 20 amino acidsB. Experiment1. ==========2. See bottomIII. S.W. Fox 1969 on ,Uni of MiamiA. Heated amino acids to 140 degrees Celsius1. 70 degrees C if phosphoric acid presentB. In lab, 18 amino acids heated like this C. Forms chains1. ProteinoidsD. In field1. Hawaiian volcanoesa. Lava and cinders – amino acids in vapors proteinoids when heated by lava2. Mixtures of hot proteinoids and cool slowly form into microspheresa. Film-like outer wallb. Can swell or shrink with water pressurec. Can “bud” or divided. Sometimes aggregate into filamentse. Have their own microenvironmentf. Streaming movements at internal particlesIV. VirusesA. Most of the existence: virion1. Crystal-like structureB. But, start replicating when cell invadedV. Eckward Wimmer 2002, Suny Stony BrookA. Polio virusesB. Synthesized the polio virusVI. When did life begin?A. Asteroid bombardment during Haedean ~4 BAB. We know that life was there by 3.8 BAVII. Where did life start?A. Need a lack of free O21. Oxygen is a volatile substancea. Oxidizes thingsB. Water vapor in upper atmosphere1. Bombarded by ultraviolet light form space2. Source of free O2C. Eventually, photosynthesis ints of O2D. Life could not have originated on Earth’s surfaceE. Ridges1. Cold seawater going through2. Magma rises3. Heat up rock4. Causing Hydrothermal VentsF. Mid Oceanic Ridges1. Enormous2. Anoxica. No O23. Organic compounds dissolve readily4. Abundant phosphorus compounds5. Metals – nickel, zincElectrodeWater Vapor„atmospher“GasesCondensorBoilWaterSammple6. Clay minerals used as substrate for assembly of organic molecules G. Chemoautotrophs1. ChemosynthesisVIII. Life starts between 4.0 BA and 3.8 BAA. First evidence 3.8BAB. First fossils 3.5 BAC. First stromatolites 3.2
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