8Th Science 1St Semester Test

Front 1

What are fossils?

Back 1

the preserved remains or traces of organisms that lived in the past

Front 2

What does the study of fossils allow for?

Back 2

describe past environments and the history of life

Front 3

What is the relative age of a rock?

Back 3

its age compared with the ages of other rocks

Front 4

What forms of life evolved during the Cambrian Explosion?

Back 4

invertebrates that lived in the sea

Front 5

Earth's earliest atmosphere lacked which gas that is necessary for life as we know it to exist today?

Back 5

oxygen

Front 6

The climate in the center of Pangaea was probably

Back 6

hot, dry desert climate

Front 7

What describes the climates of Europe and North American during the 1.8 million years of the Quaternary Period?

Back 7

a series of ice ages followed by periods when the glaciers melted

Front 8

What is a petrified fossil?

Back 8

a fossil formed when minerals replace all or part of an organism

Front 9

What is the age of an intrusion of igneous rock in relation to the sedimentary rock layers through which it passes?

Back 9

always younger

Front 10

Originally, the geologic time scale placed Earth's rocks in order how?

Back 10

relative age

Front 11

When did Earth's atmosphere, oceans, and continents form?

Back 11

Precambrian Time

Front 12

What are animals that spend part of their lives in water?

Back 12

amphibians

Front 13

What is stress that pushes a mass of rock in two opposite directions?

Back 13

shearing

Front 14

The part of the fault that lies below the other parts

Back 14

footwall

Front 15

In a strike-slip fault, the rocks on either side of the fault slip past each other sideways with little

Back 15

up-or-down motion

Front 16

The type of stress force that produces reverse faults.

Back 16

Compression

Front 17

The point beneath Earth's surface where rock breaks under stress and triggers and earth quake is called the

Back 17

focus

Front 18

The type of seismic waves that arrive at the surface first and move by compressing and expanding the ground like an accordion are called

Back 18

P waves

Front 19

The rating system that estimates the total energy released by an earthquake is called the

Back 19

moment magnitude scale

Front 20

A force that acts on rock to change its shape or volume is called

Back 20

stress

Front 21

S waves are also known as

Back 21

secondary waves

Front 22

Compared to P waves and S waves, surface waves move

Back 22

slower

Front 23

What scale would most likely be used to tell how much earthquake damage was done to homes and other buildings?

Back 23

Mercalli scale

Front 24

The three major fossil fuels are coal, oil, and

Back 24

natural gas

Front 25

Fossil fuels are considered nonrenewable resources because they

Back 25

take hundreds of millions of years to form

Front 26

Wind energy is actually an indirect form of

Back 26

solar energy

Front 27

In a nuclear power plant, what is used to change water into steam?

Back 27

heat released from nuclear fission reactions

Front 28

What is efficiency?

Back 28

the percentage of energy that is actually used to perform work

Front 29

Fossil fuels are energy-rich because they contain

Back 29

hydrocarbons

Front 30

Coal is a solid fossil fuel formed from

Back 30

decaying plant remains

Front 31

In one hour, Earth receives enough solar energy to satisfy the energy needs of the world for how long?

Back 31

a year

Front 32

In which part of a nuclear power plan does nuclear fission occur?

Back 32

reactor vessel

Front 33

One example of an energy-efficient device is a

Back 33

fluorescent light bulb

Front 34

The most plentiful fossil fuel in the United States is

Back 34

coal

Front 35

Which fossil fuel produces the lowest levels of most air pollutants?

Back 35

natural gas

Front 36

Factories where crude oil is separated into fuels and other products are called

Back 36

refineries

Front 37

What is the results of using fossil fuels more rapidly than they are formed?

Back 37

The reserves will eventually be used up

Front 38

Which is an examples of a biomass fuel?

Back 38

wood

Front 39

The intense heat from Earth's interior that warms the magma beneath Earth's surface is called what?

Back 39

geothermal energy

Front 40

A layer of material that helps block the transfer of heat between the air inside and outside a building is called

Back 40

insulation

Front 41

What erosion begins when runoff from rain fall flows in a thin layer over the land in a kind of erosion is called what?

Back 41

sheet erosion

Front 42

The process by which natural forces move weathered rock and soil from one place to another is called

Back 42

erosion

Front 43

Landslides, mudflows, slump, and creep are all examples of

Back 43

mass movement

Front 44

A river flowing across a wide flood plain begins to form looplike bends called

Back 44

meanders

Front 45

Deltas are built up by

Back 45

deposition

Front 46

The process in which rock fragments freeze to the bottom of a glacier and then are carried away when the glacier moves is called

Back 46

plucking

Front 47

The energy that produces ocean waves comes from

Back 47

wind blowing across the water's surface

Front 48

The process by which wind removes surface materials is called

Back 48

deflation

Front 49

a wide sloping deposit of sediment formed where a stream leaves a mountain range is called a

Back 49

alluvial

Front 50

Which of the following is evidence that an area was once covered by a glacier?

Back 50

U-shaped valley

Front 51

Mass movement is caused by

Back 51

gravity

Front 52

Where a river flows from an area of harder rock to an area of softer rock, the softer rock may wear away, eventually forming a drop called a

Back 52

waterfall

Front 53

After the last ice age, stranded ice blocks left behind by the continental glacier melted and formed

Back 53

kettles

Front 54

A ridge of till located at the farthest point reached by a glacier is called a

Back 54

terminal moraine

Front 55

If waves erode the soft rock along the based of a steep coast, the result may eventually be a landform called a

Back 55

wave-cu cliff

Front 56

Wind carrying sand grains deposits the sand when the wind

Back 56

slows down or hits and obstacle

Front 57

Particles of clay and silt eroded and deposited by the wind are called

Back 57

loess

Front 58

In deserts, deflation can sometimes create an area of rock fragments called a

Back 58

desert pavement

Front 59

According to Wegener's hypothesis of continental drift,

Back 59

the continents were once joined together in a single landmass

Front 60

What is Pangaea?

Back 60

the name of the supercontinent that existed millions of years ago

Front 61

Any trace of an ancient organism that has been preserved in rock is called a

Back 61

fossil

Front 62

What technology did scientists use in the mid-1900s to map the mid-ocean ridge?

Back 62

sonar

Front 63

In sea-floor spreading, molten material rises from the mantle and erupts

Back 63

along mid-ocean ridges

Front 64

Old oceanic crust is more dense than new oceanic crust because it is

Back 64

cool

Front 65

The geological theory that states that pieces of Earth's lithosphere are in constant, slow motion is the theory of

Back 65

plate tectonics

Front 66

A place where two plates slip past each other, moving in opposite directions, is known as a

Back 66

transform boundary

Front 67

A collision between two pieces of continental cruse at a converging boundary produces a

Back 67

mountain range

Front 68

How did scientists discover that rocks farther away from the mid-ocean ridge were older than those near it?

Back 68

by determining the age of rock samples obtained by drilling on the sea floor

Front 69

What did scientists in a submersible see when they observed the mid-ocean ridge?

Back 69

rocks formed by the rapid hardening of molten material

Front 70

Mid-ocean ridges are

Back 70

found in all of Earth's oceans

Front 71

The process by which the ocean floor sinks beneath a deep-ocean trench and back into the mantle is known as

Back 71

subduction

Front 72

A rift valley forms as a

Back 72

divergent plate boundary

Front 73

The place where two plates come together is known as a

Back 73

convergent boundary

Front 74

Geologists infer from the rounded, eroded shapes of the Appalachian Mountains that

Back 74

the mountains have been eroding for millions of years

Front 75

A marble statue is left exposed to the weather. Within a few years, the details on the statue have begun to weather away. This weathering probably is caused by

Back 75

carbonic acid in rainwater

Front 76

Granite lasts a long time when it is used for building in areas where

Back 76

the climate is mostly cool and dry

Front 77

The most important factors in determining the rate of weathering are

Back 77

rock type and climate

Front 78

When earthworms add their wastes to the soil, then die and decay in the soil, they are contributing to the formation of

Back 78

humus

Front 79

In a cross section of soil, the B horizon consists of

Back 79

clay, minerals, and little humus

Front 80

Most of the work of mixing humus within the soil is done by

Back 80

earthworms

Front 81

The type of soil called loam is made up of

Back 81

nearly equal amounts of silt, sand, and clay

Front 82

What can cause the loss of soil that is not protected by plant cover?

Back 82

erosion by water or wind

Front 83

Plowing removed the grass from the Great Plains and exposed the soil. What effect did this have when a drought struck the Great Plains during the 1930s?

Back 83

It helped to cause the Dust Bowl

Front 84

What kid of weathering causes the mineral composition of rocks to change?

Back 84

chemical weathering

Front 85

Frost wedging causes mechanical weathering of rock by means of

Back 85

freezing and thawing of water

Front 86

The agent of mechanical weathering in which rock is worn away by the action of other rock particles is called

Back 86

abrasion

Front 87

A hot and wet climate causes weathering to take place

Back 87

rapidly

Front 88

A permeable rock weathers easily because it

Back 88

contains many small, connected airspaces

Front 89

Soil formation begins with the weathering of

Back 89

bedrock

Front 90

Soil that is rich in humus has high

Back 90

fertility

Front 91

In which soil layer would you find loam that is rich in humus?

Back 91

A horizon

Front 92

The texture or particle size of soil determines

Back 92

how much air and water the soil can hold

Front 93

Living organisms in soil help to

Back 93

mix the soil and make humus

Front 94

What term describes the management of soil to prevent its destruction?

Back 94

soil conservation

Front 95

The practice of plowing fields along the curves of a slope is called

Back 95

contour plowing

Front 96

In conservation plowing, why are dead weeds and stalks of the previous year's crop left in the ground?

Back 96

to retain moisture and hold the soil in place