26. The Tree of Life
Terms
undefined, object
copy deck
- absolute dating
- Dating that involves years, rather than "before" and "after"
- Paleozoic
- An era with the cambrian to permian eras occuring 542 to 251 M years ago, marked by the explosion of animals, plants and reptiles
- Mesozoic
- An era with the Triassic, Jurassic and Cretaceous periods from 251 to 65.5 M years ago, marked by dinosaurs, gymnosperms and angiosperms, as well as the mass extinction at the end of the period
- Permian
- A period in the paleozoic era from 299 to 251 M years ago marked by reptiles, insects and the extinction of many marine and terrestrial organisms possibly triggered by volcanic activity and a drop of oxygen in oceans
- carbon-14
- A radioactive isotope of carbon that decays to nitrogen-14
- Pangea
- The supercontinent that existed from 250 M years ago (end of the Paleozoic era) before drifting back apart
- index fossils
- Similar fossils that allow strata in different locations to be correlated
- stromatolites
- Rocklike structures composed of bacteria and sediments; the oldest known fossils from 3.5 B years ago
- iridium
- The contents of a thin layer of clay separating the Mesozoic and Cenozoic eras
- ribozyme
- RNA that has enzyme-like catalytic functions
- Archaean
- 1st eon from 4600 to 2500 M years ago, includes the origin of Earth and prokaryotes
- genetic annealing
- A process in which horizontal gene transfers occur between bacterial and archaean lineages, possibly helping form eukaryotes
- Precambrian
- Period of eons that includes Archaean and Proterozoic
- potassium-40
- Radioactive isotope present in volcanic rocks that decays to argon-40
- radiometric dating
- Dating based on the decay of radioactive isotopes
- Cenozoic
- Era including the Paleogene and Neogene periods, marked by mammals, angiosperms and humans, began 65.5 M years ago
- Proterozoic
- 2nd oldest eon from 2500 to 542 M years ago, includes algae, and invertebrate animals
- carbonaceous chondrites
- Meteorites that contain 1-2% carbon compunds w/ amino acids of D and L isomer
- magnetic reversal
- An event in which the magnetic field of the planet flips
- protobionts
- Aggregates of abiotically produced molecules surrounded by a membrane-like structure
- Phanerozoic
- Current eon, marked by the Paleozoic, Mesozoic and Cenozoic eras
- snowball Earth hypothesis
- A hypothesis that states from 750 to 570 M years ago there was a severe ice age that iced the seas, confining life to deep-sea vents, hot springs and thin ice areas
- Cretaceous
- Period in the Mesozoic era from 145.5 to 65.5 M years ago, marked by angiosperms as well as the mass extinction of dinosaurs at its end, possibly caused by an asteroid hit
- endosymbiont
- A cell that lives within another cell