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Flashcards in Chapter 8 Fossils Deck (41)
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1

Fossil

Naturally preserved evidence of life,
Whole body isn't fossilized, soft parts decay or get eaten. Hard parts buried in sediment slowly turn into rock

2

Mold

Hardened sediment that form around organism

3

Cast

Model of organism that forms when sediment fills a mold and hardens

4

What happens to an organisms stored energy when it dies?

Remains in organism cells; temperature and pressure layers above change dead organism into fossil fuels

5

Fossil fuels

Energy rich resources form from buried remains of organisms that were once alive

6

Petroleum & natural gas

Mainly form from organism that lived in the ocean

7

Coal

Form from decayed swamp plants piling up, decaying, and pressed into coal

8

Where are fossil fuels found

Since petroleum and natural gas form mainly from organisms that lived in the ocean, these fossil fuels are found where oceans used to be. Coal deposits found where swamps were

9

How old is the earth?

4.6 billion yrs old

10

Why is no rock on earths surface as old as the earth?

Rock is constantly being created and destroyed

11

Index fossils

Fossils of organisms that lived during a relatively short time span, are common, and found in many places

12

What does it mean when the same fossil types are found in widely separate places on Earth?

Land masses used to be in different places

13

Continental drift

Process by which continents have moved slowly from one position to another

14

How can you find out what kinds of ecosystems existed in certain areas in the past?

Look at fossils

15

How do scientists study organisms that are extinct?

Study their fossils

16

Fossil record

Shows how the kinds organisms that lived on Earth have changed over time

17

Mass extinction

Period in which a large number of species become extinct relatively quickly

18

Do scientists know what caused a mass extinction?

No, they think any event greatly changing the environment can cause a mass extinction

19

How do some species avoid extinction?

Adapted

20

Examples of fossils

Preserved remains, mold, cast, animal's burrow, animal's waste, footprint

21

Why are animals with hard parts parts more likely to become than animals with soft parts?

Soft parts decay or get eaten

22

Explain how fossil fuels form?

Animal dies but stored energy remains, overtime it's buried by sediment. Temperature & pressure slowly turn remains into fossil fuels

23

Why has natural gas use replaced coal use?

Burns cleaner producing less air pollution

24

What can be assumed about an area that is rich with petroleum?

It was an ocean

25

What can scientists learn from the fossil record?

How earth has changed over time

26

What do you know about different layers of rock that you see?

Oldest layers are on bottom, youngest on top

27

A place in CA where organisms are trapped in tar and become fossilized

Labretarpits

28

When an organism dies, stored energy in its body is changed by heat and pressure into what?

Fossil fuels

29

Organism with these parts are more likely to form fossil fuels

Hard parts

30

Model formed when sediment fills a mold

Cast