BIOL 1202 Study Guide - Radiometric Dating, Autotroph, Archaea
Document Summary
Chapter 25: the history of life on earth. Conditions on early earth: atmosphere, co2; ch4; nh3; h2s; h2o, no free oxygen, abundant energy to drive reactions, frequent storms w/ much lightening, frequent volcanic eruptions, frequent meteor impacts, uv light from the sun. Life on earth arose as a result of physical-chemical processes. Life is so complex that it must have been created by a supernatural being. Testable hypotheses explaining the origin of life: abiotic synthesis of small organic molecules, joining these molecules into polymers, packaging these molecules into protobionts , the origin of self-replicating molecules. Alternate hypothesis: first organic compounds have been synthesized near hydrothermal vents, extraterrestial origin. Abiotic synthesis of polymers: small organic molecules polymerize when they are concentrated on hot sand or clay. Protobionts: aggregates of abioically produced molecules surrounded by a membrane, liposomes can form when lipids or other organic molecules are added to water.
