Module 7

Question 1

1a. Define: Fossil

Answer 1

The preserved remains of a once-living organism

Question 2

1b. Define: Petrifaction

Answer 2

The conversion of organic material into rock

Question 3

1c. Define: Resin

Answer 3

A think, slowly flowing liquid produced by plants that can harden into a solid

Question 4

1d. Define: Extinct

Answer 4

A term applied to a species that was once living but now is not

Question 5

2. When a plant or animal dies, what is the most likely thing that will happen to its remains?

Answer 5

they will decompose

Question 6

3. Which forms first: a fossil mold or a fossil cast?

Answer 6

A fossil mold forms first.

Question 7

4. Describe the process of a cast forming, indicating when the mold has formed and when the cast has formed.

Answer 7

The remains of a plant or animal are encased in sediment, and the sediment eventually hardens into rock. As the remains of the plant or animal disintegrate, a hole is left in the rock, in the shape of the original remains. That is the mold. The mold might fill up with sediment or magma later and, when the filling hardens, it forms a cast.

Question 8

5. What is required in order for petrifaction to occur?

Answer 8

water that has a lot of minerals in it

Question 9

6. Why does petrifaction usually produce fossils with more information than fossil casts?

Answer 9

because fossil fasts retain only the shape and outer details of the fossil; when a fossil is petrified, its components are replaced with minerals; this means the entire fossil is preserved, which gives us more information than just the shape and outer details of the fossil

Question 10

7. Can you learn much about the thickness of an organism from carbonized remains?

Answer 10

no

Question 11

8. What type of organism is most likely to leave carbonized remains?

Answer 11

plants

Question 12

9. What is so nice about fossils that have been encased in amber or ice?

Answer 12

Thus, tissue and other soft plants tend to be preserved

Question 13

10. What are the four general features of the fossil record?

Answer 13

I. Fossils are usually found in sedimentary rock. Since most sedimentary rock is laid down by water, it follows that most fossils were laid down by water.

II. The vast majority of the fossil record is made up of hard-shelled creatures like clams. Most of the remaining fossils are of either water-dwelling creatures or insects. Only a tiny, tiny fraction of the fossils we find are of plants, reptiles, birds, and mammals.

III. Many of the fossils we find are of organisms that are still alive today. Many of the fossils we find are of organisms that are now extinct.

IV. The fossils found in one layer of stratified rock can be considerable different from the fossils found in another layer of stratified rock.

Question 14

11. What kinds of creatures make up the vast majority of the fossil record?

Answer 14

Clams and other hard-shelled animals

Question 15

12. Approximately how many species of plants and animals have gone extinct in the last 400 years: a hundred, a thousand, ten thousand, or a hundred thousand?

Answer 15

a thousand

Question 16

13. What is a trilobite? Are trilobites extinct?

Answer 16

a creature that lived in the water and was covered in a hard outer covering; extinct

Question 17

14. What is a placoderm? Are placoderms extinct?

Answer 17

a kind of fish; It was much like the fish we see today, but its head was covered in hard plates rather than scales; extinct

Question 18

15. What is the uniformitarian explanation for how most sedimentary rocks formed?

Answer 18

sediments are laid down slowly over millions of years; Eventually, conditions change and the sediments harden to forms rocks. The conditions during which the sediments were laid down determine the type of sediment, which in turn determines the kind of rock formed.

Question 19

16. What is the catastrophist explanation for how most sedimentary rocks formed?

Answer 19

formed in the worldwide flood; The depth, speed, and direction of the flood waters determined what type of sediments were laid down, which in turn determined the kind of rock formed.

Question 20

17. What is the uniformitarian explanation for why different fossils are formed in different straits?

Answer 20

the different fossils found in different layers result from the fact that different plants and animals existed at different times in any given region

Question 21

18. What is the catastrophist explanation for why different fossils are formed in different straits?

Answer 21

the different fossils in different layers are the result of the fact that different kinds of organisms were trapped and preserved during different stages of the flood

Question 22

19. What major speculation must uniformitarians make when studying geology?

Answer 22

how millions of years of time affect the processes we see working today

Question 23

20. What major speculation must catastrophists make when studying geology?

Answer 23

the nature of the worldwide flood