Chapter 8 science study guide

Question 1

the study of structure of planet Earth and the forces that make and shape the Earth

Answer 1

geology

Question 2

occurs when running water, ice, or windbreak down rocks and carry the pieces away

Answer 2

erosion

Question 3

states that the geologic processes that operate today also operated in the past

Answer 3

uniformitarianism

Question 4

rocks that form when molten material form beneath Earth’s surface cools and hardens

Answer 4

igneous rock

Question 5

a rock made of sediments that have been deposited and then pressed together to form a solid rock

Answer 5

sedimentary rock

Question 6

a rock that forms when an existing rock is changed by heat, pressure, or chemical reactions

Answer 6

metamorphic rock

Question 7

a series of processes on and beneath the Earth’s surface that slowly change rocks from one kind to another

Answer 7

rock cycle

Question 8

molten material beneath Earth’s surface

Answer 8

magma

Question 9

magma that flows on to Earth’s surface

Answer 9

lava

Question 10

a rock’s age compared to the ages of other rocks

Answer 10

relative age

Question 11

the number of years since a rock has been formed

Answer 11

absolute age

Question 12

states that in horizontal sedimentary rock layers the oldest layer is at the bottom. Each higher layer is younger than the layers below it

Answer 12

law of superposition

Question 13

lava that hardens on the surface

Answer 13

extrusion

Question 14

when the magma cools and hardens in to a mass of igneous rock

Answer 14

intrusion

Question 15

a break in Earth’s crust

Answer 15

fault

Question 16

the surface where new rock layers meet a much older rock surface beneath them

Answer 16

uncomformity

Question 17

a piece of rock that is contained in another rock

Answer 17

inclusion

Question 18

a fossil that tells the relative ages of the rock layer in which they occur

Answer 18

index fossil

Question 19

all the matter you see, including rocks, is made of tiny particles called _____

Answer 19

atom

Question 20

When all the atoms in a particular type of matter are the same, the matter is an _________

Answer 20

element

Question 21

when the atoms of one element break down to form atoms of another element

Answer 21

radioactive decay

Question 22

The time it takes for half of the radioactive atoms to decay

Answer 22

half-life

Question 23

the 12 pieces that the outer layer of the Earth is made of

Answer 23

plates

Question 24

states that Earth’s landmasses have changed position over time because they are part of plates that are slowly moving

Answer 24

the theory of plate tectonics

Question 25

the very slow movement of continents

Answer 25

continental drift

Question 26

a record of the life forms and geologic events in Earth's history

Answer 26

geologic time scale

Question 27

the three long units between Precambrian time and the present.

Answer 27

Eras

Question 28

Eras subdivion

Answer 28

periods

Question 29

animals without backbones

Answer 29

invertebrates

Question 30

animals with backbones

Answer 30

vertebrates

Question 31

an animal that lives part of its life on land and part of its life in the water

Answer 31

amphibian

Question 32

animals that have scaly skin and lay eggs with tough, leathery shells

Answer 32

reptiles

Question 33

a time in which many types of living things become extinct at the same time

Answer 33

mass extinction

Question 34

a warm-blooded vertebrate that feeds its young milk

Answer 34

mammal