1. Chapter 2, Section 1: Planet Earth
The Physical World
Chapter 2, Section 1: Planet Earth

2. Important Vocabulary
Hydrosphere: the oceans, lakes, river, and other water bodies.
Lithosphere: the land on the Earth’s surface.
Atmosphere: a layer of gases extending above the earth’s surface.
Biosphere: the part of the Earth that supports life.
Continental Shelf: an underwater extension of the coastal plain.

3. The Solar System The sun is its epicenter.
Inner Planets (Terrestrial): Mercury, Venus, Earth, and Mars.
Outer Planets (Gaseous): Jupiter, Saturn, Uranus, Neptune, and Pluto*.
Other Objects: Asteroids, Comets, and Meteoroids.

4. Planet Earth The largest inner planet.
Its surface is made up of 70% water (hydrosphere).
The lithosphere is the other 30%.
The atmosphere contains 78% nitrogen and 21% oxygen.
The biosphere supports all life on Earth.

5. Chapter 2, Section 2: Forces of Change
The Physical World
Chapter 2, Section 2: Forces of Change

6. Important Vocabulary Core: super-hot solid at Earth’s inner center.
Mantle: thick layer of hot, dense rock.
Crust: the rocky outer layer of Earth’s surface.
Continental Drift: theory that the continents were once joined together and then slowly drifted apart.
Plate Tectonics: refers to all of the physical processes that create many of Earth’s physical features.

7. Important Vocabulary
Magma: molten rock pushed up from the mantle during shifting plate tectonics.
Subduction: heavier plate goes underneath lighter plate.
Accretion: pieces of the Earth’s crust come together.
Spreading: the moving apart of sea plates.
Fold: the bending of layers of rock as plates push together.
Fault: cracks in the Earth’s crust.

8. Important Vocabulary
Faulting: occurs when the folded land cannot bend anymore.
Weathering: the breakdown of rock.
Erosion: the wearing away of Earth’s surface.
Glacier: large ice bodies which move across Earth’s surface.
Moraine: debris left behind by melted glaciers.

9. Inside the Earth
Three layers: the core, the mantle, and the crust.

10. Continental Drift Earth was original a Pangaea or supercontinent.
Continental drift separated the land masses.

11. Plate Movement
Shifting plates can lead to earthquakes and volcanic eruptions.
Plate movement is also caused by sea- floor spreading.

12. Movement Types

13. External Forces
External forces, erosion(s), can alter the earth’s surface.
Weathering can physically or chemically alter rocks.

14. Chapter 2, Section 3: Earth’s Water
The Physical World
Chapter 2, Section 3: Earth’s Water

15. Important Vocabulary Water Cycle: the regular movement of water.
Evaporation: changing of liquid water into a vapor or gas.
Condensation: changing of water vapor into liquid water.
Precipitation: moisture which falls to the Earth.

16. Important Vocabulary
Desalination: turning saltwater into fresh, drinking water.
Groundwater: freshwater which lies beneath the Earth’s surface.
Aquifer: underground, porous rock which stores water.

17. The Water Cycle
Earth has constant water movements, which form a cycle.
The process consists of: evaporation, condensation, and precipitation.

18. Water Bodies The vast majority of water is salt (97%).
Lakes, streams, and rivers are mainly freshwater. Most not available for drinking.