Fossils Study Guide PDF

Name:___________________ Section:___________________ Geologic Time Scale/ Fossils Study Guide Parent signature___________________________________________________________ 1. _________________ is t...

Name:___________________ Section:___________________ Geologic Time Scale/ Fossils Study Guide Parent signature___________________________________________________________ 1. _________________ is the longest division in the Geologic Time Scale. a. Era b. Eon c. Period d. Epoch 2. Name the four types of Fossils. Cast Fossil True-Form Fossil Mold Fossil Trace Fossil 3. The first eon in Earth History was the _______ a. Precambrian Eon b. Proterozoic Eon c. Hadean Eon 4. What is the geologic time scale used to organize? The geologic time scale is used to organize Earth's 4.6-billion-year-old history. 5. Life appeared on Earth during _______ a. The Hadean Eon b. Precambrian Time c. A period d. An epoch 6. What is a fossil?  Name:___________________ Section:___________________ A fossil is the preserved remains or traces of ancient plants, animals, or other living things. 7. Where will the youngest fossils be found in the layers of fossil record? The youngest fossils can be found at the top of the layers. The further down, the older the fossil. 8. How are rock layers helpful in understanding Earth's history? Rock layers are helpful in understanding Earth's history by showing us how the Earth's surface has changed over time. Fossils in these layers help us learn about ancient plants and animals, while different rocks give clues about the environment and climate. 9. Which of the following is a period of the Mesozoic Era? a. Precambrian b. Jurassic c. Neogene d. Ordovician 10. Which of the following is NOT an Eon? a. Archean b. Proterozoic c. Hadean d. Paleocene 11. Which division on the geologic time scale is the shortest? a. Epoch b. Era c. Eon d. Period  Name:___________________ Section:___________________ 12. What type of animal lived ONLY during the Mesozoic Era? a. Mammals b. Non- Avian dinosaurs c. Birds and Mammals d. All of them 13. How are Mold Fossils made? Mold Fossils are formed from an organism that dies and is buried. The soil hardens into stone around it, preserving the shape of its body even after it decomposes. 14. How are Trace Fossils made? Trace fossils are formed from an organism that went on living but left something behind (like a footprint). The print hardened into stone to form a fossil. 15. How are true-form fossils made? True- form fossils are formed from the body of an organism that is unable to decay and is preserved when it is frozen in ice or trapped in amber or tar. 16. How are cast fossils made? Cast fossils are formed from water carrying dissolved minerals seeping through the rocks to fill a mold. The minerals harden to form the shape of the organism. 17. What is the difference between a mold fossil and a cast fossil? Cast fossils are formed from water carrying dissolved minerals seeping through the rocks to fill a mold while Mold fossils are formed from soil that hardens into stone from a decomposed organism.  Name:___________________ Section:___________________ 18. What does the law of superposition state? The Law of Superposition states, when rocks are stacked in layers, the oldest rocks will be on the bottom and the newest rocks will be on top. Scientists use this law to better understand the age of fossils. Answer the following questions in complete sentences. 19. Describe the Hadean Eon and why there aren’t any fossils There was likely no life during the Hadean Eon because the Earth was extremely hot, with a molten surface to where life would not be able to survive these conditions. 20. Describe the Archean Eon. In the Archean Eon, most of the atmosphere was carbon dioxide and the first signs of life started to appear. 21. Describe the Proterozoic Eon and how the atmosphere changed. The Proterozoic Eon was a period in time where the Earth had a change in the atmosphere. Oxygen became present because of photosynthetic organisms. This allowed for the development of multicellular organisms. 22. Choose one of the three Eras (Paleozoic, Mesozoic, or Cenozoic Era) and describe the significant geological events that occurred in that Era. The Paleozoic Era started with the Cambrian Explosion. This led to the appearance of more complex life, like fish developing teeth. The Mesozoic Era was known as the age of reptiles. This is the only Era where non-avian dinosaurs existed.  Name:___________________ Section:___________________ The Cenozoic Era was known as the age of mammals. The climate warmed up and new mammal groups came about like whales, bats, and rodents. Answer is B  Name:___________________ Section:___________________ Answer is C