Mass extinction {Ans: event in which many types of living things become extinct at the same time (ex. End of Ordovician, Late Denovian, Late Permian, Late Triassic, Cretaceous- Tertiary, Pleistocene)}closed system {Ans: system that exchanges energy but not matter (ex: H2O system and N cycles)}Over consumption {Ans: resource use that is unsustainable in the long term; obtaining more products than people need}4 major pollutant sources {Ans: fossil fuels domestic waste industrial waste agricultural waste}sustainable yield {Ans: rate at which a renewable resource can be used indefinitely without reducing its available stock, rate of increase in natural capital, which can be exploited without depleting original stock or potential for replenishment}open system {Ans: system that exchanges matter and E (ex: ecosystem)}