| Question |
Answer |
| a group of things or parts that work together for a common purpose |
system |
| a low area between hills and mountains where a river often flows |
valley |
| the change of water from one state to another as it travels through Earth's atmosphere and its surface |
water cycle |
| the process of rock breaking down into smaller pieces |
weathering |
| an object in space that produces its own heat and light |
star |
| something built by people |
structure |
| a star around which the Earth and other planets in our solar system revolve |
Sun |
| dark spots on the surface of the sun that are cooler than their surrounding areas |
sunspots |
| a slanted surface; a surface that is not flat or level |
slope |
| release enormous amounts of magnetic energy that can and sometimes do affect the electronic equipment on Earth |
solar flare |
| arise from the intense heat of the corona; travel outward from the Sun through our Solar System |
solar winds |
| violent explosions of streams of hot gas |
solar prominence |
| the complete trip a planet makes around the Sun; Earth's is 365 1/4 days |
revolution |
| the spinning of a planet or object in space on its axis |
rotation |
| a line separating the land and the oceans; zero elevation |
sea level |
| tiny bits of rock, shell, soil, sand, or dead plants |
sediment |
| elevated areas of level land |
plateau |
| the part of a river channel where the water moves rapidly over obstacles, such as large boulders |
rapids |
| to use a material or substance again, usually in another form or way |
recycle |
| resources that can be replaced in a short period of time, such as plants, animals, water, oxygen, and soil |
renewable resources |
| the cyclical change in the way the moon reflects the Sun's light as it revolves around Earth |
phases of the moon |
| the highest point or top of a mountain |
peak |
| broad, flat areas of land not far above sea level |
plains |
| large objects that revolve around a star |
planets |
| a natural object that orbits a planet; a satellite |
moon |
| a nonrenewable resource that is found under ground, used as a fuel and is a burnable gas |
natural gas |
| resources that cannot be replaced in a short period of time, such as oil (petroleum), natural gas, coal, and minerals |
nonrenewable resources |
| the path that one object takes around another object |
orbit |
| drawings, usually on a flat surface, of an area or the features of an area |
map |
| sudden downhill movement of rock, sediment, or soil; such as a landslide or mudslide |
mass movement |
| a curve or loop in a river |
meander |
| a representation, generally in miniature, to show the construction or appearance of something |
model |
| resources that cannot be used up, such as wind, sunlight, and ocean tides |
inexhaustible resources |
| to give an explanation |
interpret |
| a shape of the land |
landform |
| a natural or constructed embankment along a stream that protects land from flooding |
levee |
| nonrenewable resources that formed from the remains of decayed plants and animals millions of years ago |
fossil fuels |
| a slab of ice that moves slowly over the land |
glacier |
| the force that pulls all objects in the universe towards each other |
gravity |
| a network of horizontal and vertical lines that form squares |
grid |
| crack in Earth's crust |
fault |
| sudden rush of water over land after a heavy rain |
flash flood |
| a very heavy flow or overflow of water over land |
flood |
| land that is covered with water during a flood |
floodplain |
| substances that make up or come from the Earth, such as water, rocks, and air |
Earth materials |
| shaking of Earth caused by the movement of the crust |
earthquake |
| height above sea level |
elevation |
| movement of Earth materials by water, wind, ice, and other natural forces |
erosion |
| a barrier that obstructs or does not allow, the flow of water |
dam |
| a fan-shaped deposit of materials that is found at the mouth of a river or stream |
delta |
| the process by which eroded materials settle in another place |
deposition |
| third planet from the Sun; only known planet that contains life |
Earth |
| center of the Earth |
core |
| the atmosphere of the Sun that can only be seen during a solar eclipse |
corona |
| outer layer of Earth that is made up of solid rock; also called the lithosphere |
crust |
| any motion of an object, sequence or process that repeats itself |
cycle |
| fan-shaped deposit of Earth materials on dry land |
alluvial fan |
| an imaginary line that a planet, or object in space, spins on |
axis |
| bottom of a mountain or other landform |
base |
| a V-shaped valley eroded by a river or stream |
canyon |