Biology 1002B Lecture Notes - Lecture 2: Abiogenesis, Homochirality, Stromatolite
8 Feb 2017
School
Department
Course
Professor
Document Summary
How old is the earth, and when do we think life developed. Stromatolites (3. 5 bya: produced by microbial activity of cyanobacteria (not necessarily first life) Earliest conclusive evidence of life (formed 3. 5 bya) Fossilized remains of ancient cyanobacterial mats that carried out photosynthesis by the water-splitting reaction. Found in habitats characterized by warm shallow water most common in australia. What are the four major developments that need to take place to make a living cell: abiotic synthesis, heritable information (transfer from parent to daughter cell, formation of cells, metabolism (energy) Know about geophysical (composition of earth) and chemical stage (formation of molecules in abiotic atmosphere), don"t know about biological (polymerization) Conditions in the primordial atmosphere, why were they conducive to the development of complex molecules. Hypothesis 2: deep sea vents: life originated in hypothermal vents, nutrient rich, 300 c water, reduced molecules; methane, ammonia, h2s. Hypothesis 3: extraterrestrial origins: key organic molecules came from space from meteors (organic molecule rich)
