Science Unit 6 Test

1. When the last of its kind dies, a species is _______.

• extinct
• cast
• fossil
• index fossil
• mold

2. The remains or traces of a plant or animal that lived long ago is a(n) _________.

• fossil
• cast
• extinct
• index fossil
• mold

3. An event that results in the dying off of many species is called a(n) _______.

• mass extinction
• cast
• fossil
• extinct
• index fossil

4. An impression of an organism, formed when sediment hardens around the organism, is called _______.

• mold
• cast
• fossil
• extinct
• index fossil

5. A model of an organism, formed when sediment fills a mold and hardens, is a(n) ________.

• cast
• fossil
• extinct
• index fossil
• mold

6. A fossil of a type of organism that lived in many places during a relatively short time span is called a(n) ________.

• index fossil
• cast
• fossil
• extinct
• mold

7. Not every animal or plant becomes a fossil when it dies. Which event best helps a fossil form?

• Water washes away dirt
• animals eat the soft tissues
• wind blows the dead organism away
• sediment quickly buries the dead organism

8. Josh read about a land animal whose fossils were found in similar rock layers in Africa and South America. What can he conclude from this discovery?

• Animal fossils all look alike
• The landmasses were once joined
• The animal swam across the ocean
• The fossils formed in an ocean and washed ashore

9.

• A
• B
• C
• D

10. Malaya was collecting fossils. She found one whose original material had been replaced by quartz. What type of fossil did she find?

• trace fossil
• carbon film
• petrified wood
• mummified body