Fossils Study Guide
1. Mold- imprint left by a plant or animal
2. Fossils- remains of once-living things that have been preserved
3. Cast- minerals that fill a mold and have the same shape as the
original living thing
4. Trace fossils- fossils that show how long-dead animals changed
their environments
5. What is an example of a trace fossil? Footprint
6. What animal parts would be most likely to form a fossil? Bones
7. A tree bruised in a mineral hot spring would probably from a
Petrified fossil.
8. By studying fossils of an animal’s droppings, scientists can find out
what the animal might have eaten.
9. What could NOT preserve a whole plant or animal as a fossil? Ocean
water
10.When minerals take the place of once-living materials,
petrified fossils are formed.
11.A mold forms when the remains of a dead plant or animal are washed
out of rock by water.
12. Heat and pressure may destroy most of the buried remains of a plant of animal,
leaving a thin covering called carbon film.
13. How can scientists find out how old a layer of rock is?
Scientists can compare the layers of rock, inferring that the deepest layers
are the oldest; measure and compare the amounts of original and decaying
particles to find out the age of the rock.
14. Why do scientists study fossils?
Scientists study fossils to find out more about what the Earth was like in the
past, to find out more about plants and animals that have died out.
15. Why are most fossils found in sedimentary rock?
Most fossils are found in sedimentary rock because animal or plant remains
become covered by layers of sediments, and as the sediments harden, the
fossil is formed.
16. Explain how scientists know that living things have changed over time.
By studying fossils and comparing them to living things today, scientists can
show how plants and animals have changed over time.
17. Sometimes scientists find fish buried in deserts. What do you think scientists
might infer from such a find?
Scientists might infer that the desert was once covered by an ocean.