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Life Sci - Chap 8 #2
Study Guide
| Question | Answer |
|---|---|
| What is a fossil? | traces or imprints of once living things preserved by geological processes |
| What is pressed together to form rock with a fossil inside? | sediments |
| Relative dating is…. | comparing one object to another to see what might be older - if buried deeper thought to be older |
| Absolute dating... | method of measuring the age of objects in years |
| ESSAY - Explain the differences between relative dating and absolute dating. | Relative dating compares objects / sees how deep they are buried to get an approximate age. Absolute dating is more precise - it uses carbon dating to get a specific age. |
| Time it takes half of the unstable atoms in an object to decay. | half-life |
| The four eras of the Earth | Precambrian, Paleozoic, Mesozoic, Cenozoic (P,P,M,C) |
| Species that no longer exists on Earth is……. | extinct |
| Scale that is used to represent Earth's history and organize it into manageable parts. | Geologic time scale |
| First organisms to appear on Earth did not need….. | oxygen |
| Cynobacteria ….. | produced food from light - this changed life on Earth; and are prokaryotes |
| In the Paleozoic era….. | fish and trilobites ruled the ocean |
| Reptile that dominated the Mesozoic Era | dinosaur |
| The time period that is the "Age of Mammals" | Cenozoic (the era we live in now) |
| Past mass extinctions most likely occurred because of…. | extreme climate changes |
| Example of Earth's conditions slowly changing is ……. | continents moving |
| Name for continents in one landmass surrounded by gigantic ocean | Pangea |
| Primates have….. | binocular vision and opposable thumbs |
| Thing that sets hominids apart from other primates | walking upright or bipedalism |
| Group of hominids that lived at the same time as homo sapiens | Neanderthals |
| ESSAY - Explain the differences between humans and other primates - what sets us apart? | Our skeletal features, intelligence, and walking upright set us apart from other primates. |
| What gas layer protects the Earth from the sun's radiation? | ozone layer |
| Scientists that study fossils/history of life are called…... | paleontologists |
| Plate tectonics…. | theory that continents move and were once part of a continent called Pangea |