BSC 116 Lecture Notes - Lecture 1: Charophyta, Cyanobacteria, Meristem
23 Aug 2016
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Inductive reasoning: extrapolating from observation to a generalization. Deductive reasoning: use a generalization to explain particular cases. Lecture 1: history of life on earth 25. 1-25. 3. Origin of life 3. 5bya chemical and physical processes on early earth may have produced simple cells in sequential stages. Contained water vapor and chemicals released by volcanic eruptions (no o2) Possible origins: reducing environment hypothesis (miller-urey) Or: the 1st organic compounds were synthesis=zed near submerged volcanoes and deep-sea vents. Reducing environment give rise to organic molecules. Catalytic rna molecules (ribozymes) capable of self-replication formed. Protoboints aggregates of abiotically produced molecules surrounded by a lipid membrane. Dna-based life is more stable, but resulted from rna-based life. Species that existed for a long period of time. Had hard body parts (fossilized easily, did not decomposes readily) Radiometric dating dating the strata around the fossils, not the fossils themselves. Half-life the time it takes half of the parent element to decay into its daughter element.
