GEOL 1301 Fall 2014 Lecture 14 Outline of Last Lecture I. Half-LifeOutline of Current LectureII. GeobiologyGEOBIOLOGYthe study of the interactions between biosphere and earth's physical environment.fluxthe flow of energy and matter between organisms and their environmentphotosynthesisprocess where plants use carbon dioxide and water and sunlight to produce glucose and oxygen.respirationorganisms release the energy in carbs like water and carbon dioxide.biogeochemical cycleThese notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.a pathway by which a chemical element or compound moves between the biological and environmental components of an ecosystem.microorganismssingle-celled organisms need water to live.Geneslarge molecules within the cells of every organism that encode all genetic informationThe Universal Tree of Lifeshows how all organisms are related to one another. 3 domains: bacteria, archea, and eukaryota.microfossilsThe traces of individual microorganisms preserved in rocksextremophilesmicroorganisms that live in environments that would kill other organisms. Live in oil, toxic wasteetc.acidophilesthrive in acidic environments. Miningthermophilesthrive in hot environments. Garbage landfillshyperthermophilesextremely hot enviroments.Halophileshighly saline environments. The Great Salt LakeAnaerobescompletely free of oxygen. Below ocean sedimentTwo ways microorganisms precipitate mineralsindirectly by influencing surrounding water or directly through their cell metabolismchemoautotrophsAutotrophs that derive their energy not from sunlight but from chemicals produced when minerals are dissolved.Anaerobic SedimentsMicrobial precipitation of pyrite releases iron and sulfur.Microbial Matslayered microbial communities. Occur in tidal flats, hypersaline lagoons, and hot springs. Are miniature models of the same geobiochemical cycles that occur on global scale.Stromatoliteslayered rocks that form when certain prokaryotes bind thin films of sediment together. Believed to have formed from ancient microbial mats.Prebiotic soup hypothesisPerformed experiment by Stanley Miller in 1950s, predicted that early planetary materials mightcontain amino acids. The idea that the earliest life emerged in a "soup-like" liquid environment, drawing upon energy from cosmic rays, volcanic eruptions, and Earth's internal heat.ChemofossilsThe chemical remains of organic compounds made by ancient microorganisms while they were alive.Origin of Earth's Oxygenated AtmosphereTwo steps: evolution of cyanobacteria that produced banded iron formations, build up of decomposed organic matter releasing oxygenBanded iron formationsThin, alternating layers of sediments on seafloor made up of precipitated chert and iron silicatesRed bedsUnusual stream deposits of sandstones and shales bound together by iron oxide cement, first appeared 2 billion years ago, after eukaryotic organisms.Evolutionary RadiationRapid development of new types of organisms from a common ancestor, marks beginning of phanerozoic eon. Coincides with Paleozoic and Cambrian periodCambrian explosionA burst of evolutionary origins when most of the major body plans of animals appeared in a relatively brief time in geologic history; recorded in the fossil record about 545 to 525 million years ago.Evolutionary "Big Bang"Hypothesis for Cambrian ExplosionEvolution? Development of Shells?Cause of of the Cretaceous-Tertiary Mass Extinction (aka dinosaurs)A gigantic asteroid impact resulting in global firestorm.Paleocene-Eocene Mass ExtinctionCaused by abrupt Global Warming from accumulation of methane. Paved way for the mammals to radiate into important group.Permian Mass Extinction95% of all earth's species became extinct. Cause is unknown.astrobiologythe branch of biology concerned with the effects of outer space on living organisms and the search for extraterrestrial lifehabitable zonesArea on star marked by the distances from the star at which water is a stable liquid.Challenges that modern life faces on Marslack of liquid water (ice) and also very acidic water present in