Ch. 3 Key Terms

Question 1

Geosphere

Answer 1

The solid part of Earth that consists of all rock, as well as the soil sand loose rocks on Earth’s surface.

Question 2

Hydrosphere

Answer 2

Makes up all of the water on or near Earth’s surface.

Question 3

Crust

Answer 3

Is composed almost entirely of light elements.

Question 4

Mantle

Answer 4

Is the layer beneath the crust, makes up 68 percent of the mass of Earth.

Question 5

Core

Answer 5

Earth’s innermost layer is the core. The core, which has a radius of approximately 3,400 km, is composed of the elements having the greatest density.

Question 6

Lithosphere

Answer 6

Earth’s outer layer is the lithosphere. It is a cool, rigid layer, 15 km to 300 km thick, that includes the crust and uppermost part of the mantle.

Question 7

Asthenosphere

Answer 7

is the layer beneath the lithosphere. The asthenosphere is a pliable, solid layer of the mantle made of rock that flows very slowly and allows tectonic plates to move on top of it.

Question 8

Tectonic Plate

Answer 8

The lithosphere is divided into pieces called tectonic plates that glide across the underlying asthenosphere in much the same way a chunk of ice drifts across a pond.

Question 9

Chemical Weathering

Answer 9

Wears down rocks, making them smoother as time passes.

Question 10

Erosion

Answer 10

Transports the materials elsewhere.

Question 11

Atmosphere

Answer 11

Earth is surrounded by a mixture of gases.

Question 12

Trophoshere

Answer 12

Extends to about 18 km above Earth’s surface. Almost all of the weather occurs in this layer.

Question 13

Stratosphere

Answer 13

Separated from the troposphere by the tropopause. Temperatures rise as altitude increases because ozone in the stratosphere absorbs the sun’s ultraviolet(UV) energy and warms the air.

Question 14

Ozone

Answer 14

Is a molecule made up of three oxygen atoms. Almost all the ozone in the atmosphere is concentrated in the ozone layer in the stratosphere.

Question 15

Radiation

Answer 15

Is the transfer of energy as electromagnetic waves.

Question 16

Conduction

Answer 16

Is the transfer of energy in the form of heat from a warmer object to a colder object when the objects are placed indirect physical contact.

Question 17

Convection

Answer 17

The transfer of energy that takes place when variations in temperature move the matter making up air.

Question 18

Greenhouse Effect

Answer 18

The process in which green house gases absorb and reradiate infrared radiation near the Earth.

Question 19

Water Cycle

Answer 19

The continuous movement of water into the air, onto land, and then back to water sources.

Question 20

Evaporation

Answer 20

The process by which liquid water is heated by the sun and then rises into the atmosphere as water vapor.

Question 21

Condensation

Answer 21

Water vapor forms water droplets on dust particles.

Question 22

Precipitation

Answer 22

These larger droplets fall from clouds as rain.

Question 23

Salinity

Answer 23

The salinity of ocean water is the concentration of all the dissolved salts it contains.

Question 24

Fresh Water

Answer 24

Most of the water on Earth is salt water in the ocean. A little more than3 percent of all the water on Earth

Question 25

Biosphere

Answer 25

The narrow layer around Earth’s surface in which life can exist