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Published byJulius Beasley Modified over 9 years ago
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Definition of life Order: cellular structure Crystals have structure without life
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reproduction Growth & development
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Energy utilization Response to the environment
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Evolution Darwin
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Adaptation
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Darwinian theory of evolution Over production Individual variations
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Natural selection 75% of population perished in one storm predators prey
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Artificial selection
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Composition of cells Organic molecules: Carbon is a versatile chemical element Water & oxygen
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Difficulties with other elements Weak bonds No double bonds
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Molecular components Carbohydrates: 2H/O sugar, starch, cellelus. glucos C6H12O6 Lipids: fatty acid Store energy for cells Proteins: large molecules Nucleic acids: DNA (deoxyribonucleic acid) & RNA (ribonucleic acid) Store structural information Built on amino acids. Enzymes & catalysts Regulate reaction rates Build structures Provide energy to cells fibers
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Two basic cell types Prokaryotic cells: No distinct nucleus Single cell species eg E coli or Salmonelia Eukaryotic cells: Both single cell (amkebas) complex species (plants, animals)
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Biological tree of life: five kingdoms Based on cell structures Drawin’s notes
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RNA tree of life: three domains Based on molecular structure
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The chemistry of life Metabolism: chemistry of life regulates reaction rates Atp(adenosine triphosphate) Metastable reaction +H 2 O
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Carbon and energy Heterotroph: get carbon from other organic compounds Autotroph: get carbon directly from the atmosphere Photosynthesis: sun light provides a source of energy, CO 2 Chemoheterotroph: organic molecules Chemoautotroph: inorganic chemicals, eg sulfur, iron, amonia. CO 2 Carbon is the most common raw material
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Importance of water 1)Dissolving organic molecules 2) transportation 3) ATP chemistry
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Double helix of DNA molecules
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Gene’s analysis
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DNA replication
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Genetic code
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Virus (a strand of RNA, not alive) Coronavirus: common cold, SARS
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Mutation and evolution
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extremofiles Thermofiles
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