BIOL 106 : S21 BIOL 106 Final Study Guide
Document Summary
Chapter 4 - origin of living cells on earth: outline the four overlapping stages that are hypothesized to have led to the origin of living cells, stage 1: formation of organic molecules prebiotic and abiotic. Extraterrestrial: organic molecules were present from meteorites (carbonaceous chondrites) Took place on solid surface or evaporating tidal pools. Formation of polymers on clay (monomer building blocks: stage 3: formation of a boundary that separated the polymers from the environment. Protobiont: aggregate of prebiotically produced molecules and macromolecules that acquired a boundary and allowed it to maintain internal chemical environment. Lipid bilayer, polymers inside contained into and had catalytic functions. Coacervates: droplets that form spontaneously from the association of charged polymers surrounded by water: stage 4: rna has the ability to store information and its nucleotide base sequence. Rna molecules function as ribosomes (rna that catalyze chemical reactions) Chemical selection: chemical within a mixture has special properties that causes it to increase in number.
