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24 Cards in this Set
- Front
- Back
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Chemical evolution -> ...
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first cells
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Early Earth had... (characteristics)
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- little oxygen
- more intense energy sources (lightning, volcanic activity, ultraviolet sunlight) |
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Formation of simple cells (stages)
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1. Abiotic Synthesis
2. Formation of polymers 3. Self-replicating molecules 4. Aggregation of polymers |
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Abiotic synthesis (define)
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Production (accumulation) of small organic molecules
e.g. amino acids, nucleotides (monomers) |
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Formation of polymers
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Monomer + Monomer -> protein and nucleic acids
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3. Self-replicating molecules (gives?)
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Origin of Heredity
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4. Aggregation of polymers (forms?)
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- Polymers form droplets with membranes
- Protobionts |
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Abiotic Synthesis
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Theorized by Oparing and Haldane (1920)
Inorganic molecules -> Organic molecules |
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Abiotic Synthesis (hypothesis; factors)
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- early Earth conditions favor chemical evolution
- no free oxygen (favors reduction) since oxygen attacks chemical bonds (oxidation) - energy available (intense UV radiation) - building blocks readily available: H2O, H2, CH4, NH3, CO, CO2, and N2 |
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In laboratory, Miller and Urey (1950s)
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With UV radiation
H2, CH4, H2O, NH3 -> amino acids |
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Abiotic polymerization (in laboratory)
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With heat
Amino acids + Clay -> polypeptides - Amino acids stick to the clay, a catalyst; it's easier for them to join |
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RNA can...
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self replicate
- is autocatalytic, ribozymes |
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Aggregation of polymers
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- living cells may have been preceded by protobionts
- aggregates of polymers - maintain an internal environment - exhibit some life properties: osmotic swelling and shrinking / excitability: cell is able to be stimulated by an electrical potential |
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Protobionts + RNA -> ...
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first cells
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Major lineage of life (Living organism divides into)
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Either
- prokaryotic - eukaryotic |
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Prokaryotic living organisms (example)
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Kingdom Monera
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Eukaryotic category (divisions)
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Unicellular
vs Multicellular |
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Unicellular eukaryotic living organisms (example)
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Kingdom Protista
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Multicellular category (divisions)
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Autotrophic
vs Heterotrophic |
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Autotrophic multicellular eukaryotes (example)
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King Plantae
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Heterotrophic multicellular eukaryotes (examples)
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- Absorptive Fungi
- Ingestive Animalia |
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Prokaryotes arose... (time frame)
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about 3.5 billion years ago
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Prokaryotes dominate...
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the biosphere
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A small percentage of prokaryotes cause...
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disease
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