Praxis 5005: Science

What layers is the Earth made up of?

crust/lithosphere, mantle, and core (outer than inner)

What happens to Earth as you go towards the center?

it gets denser

What happens to the temperature of the earth as you move towards the center?

the temperature increases

What are the compositional layers of the earth?

crust, mantle, core

What are the mechanical layers of the Earth?

lithosphere, asthenosphere, mesosphere, outer core, inner core

What is the Troposphere?

0–12 km above Earth. Most of Earth’s weather occurs here

What is the Stratosphere?

12–50 km above Earth. Contains the ozone layer

What is the Mesosphere?

50–80 km above Earth. Beneath the asthenosphere. It encompasses the lower mantle, where material still flows but at a much slower rate than in the asthenosphere.

What is the Thermosphere?

80–700 km above Earth

What is the Exosphere?

700–1000 km above Earth

What is the order of the Earths atmosphere?

troposphere, stratosphere, mesosphere, thermosphere, exosphere

What is the composition of the Earths atmosphere?

Nitrogen – 78%, Oxygen – 21%, Argon – .09%, Carbon dioxide – .01%, Helium – small traces, Neon – small traces, Other gases – small traces

What is the crust?

The outermost solid layer of Earth

What is the mantle?

is not liquid; it is ductile or plastic, which means that some parts of the mantle can flow under certain conditions and changes in pressure. The mantle is mainly composed of aluminum and silicates

What is the core?

The innermost layers of Earth. Earth has an outer core (liquid) and an inner core (solid). mainly composed of nickel and iron.

What is the lithosphere?

The outermost and most rigid mechanical layer of Earth. includes the crust and the top of the mantle.

What is the Asthenosphere?

Underneath the lithosphere. It is about 100km thick. This region of the mantle flows relatively easily. The mantle is NOT liquid.

What is the outer core?

A layer of liquid iron and nickel (and other elements) beneath the mesosphere. This is the only layer of Earth that is a true liquid.

What is the hydrosphere?

All the water on Earth in liquid form. For example, lakes, rivers, and oceans

What is the biosphere?

The global sum of all ecosystems and living organisms.

what is the Cryosphere?

The masses of frozen water. For example, frozen lakes, frozen rivers, frozen oceans, and glaciers

What is the Atmosphere?

gasses around the earth

What do glaciers contain?

69% of Earth’s fresh water. Ice and glaciers are part of the water cycle.

What make up 99% of the gasses in the atmosphere?

nitrogen and oxygen

How was the Earth’s atmosphere formed?

from volcanic eruptions that happened early in Earth’s history

where do meters come from?

the mesosphere

What does the ozone layer do?

absorbs 97%-99% of the sun’s ultraviolet light and is contained in the stratosphere. This layer contains high levels of ozone (O3). Two decades of scientific research has shown that human-produced chemicals are responsible for the observed depletions of the ozone layer.

What happens when we drive cars?

carbon dioxide (CO2) is released into the atmosphere. The CO2 is trapped inside the ozone layer and prevents the sun’s rays from escaping, which contributes to Earth’s increase in temperature.

What is the water cycle the result of?

a collection of connected processes that distribute water and energy throughout the Earth system in cyclic patterns

What is precipitation?

water released from clouds in the form of rain, freezing rain, sleet, snow, or hail. It is the primary connection in the water cycle that provides for the delivery of atmospheric water to the Earth.

What is condensation?

when water vapor in the air is changed into liquid water. is responsible for the formation of clouds

What is evaporation?

the process by which water changes from a liquid to a gas or vapor. the primary pathway that water moves from the liquid state back into the water cycle as atmospheric water vapor

What does divergent mean?

pulling apart

what does convergent mean?

coming together

what does subduction mean?

sideways and downward movement of the edge plate into the mantle beneath another plate

What are The Processes of the Lithosphere (Crust)?

Geologic formations are formations made from rocks that exist on the lithosphere. Examples include volcanoes, mountains, and canyons

What are mountains?

formed because of Earth’s tectonic plates smashing together.

What are volcanoes?

formed when magma from within Earth’s upper mantle erupts through the surface

what are canyons?

formed by weathering and erosion caused by the movement of rivers. also formed by tectonic activity

What are earthquakes?

caused when plates rub against each other in an opposite motion, and rock underground suddenly breaks along a fault. This sudden release of energy causes seismic waves that make the ground shake

What is the Ring of FIre?

ring of volcanoes around the outer edge of the Pacific Ocean. These volcanoes are a result of subduction of oceanic plates beneath lighter continental plates. In fact, most of Earth’s volcanoes and earthquakes happen along the Ring of Fire

What are Seismic Waves?

an elastic wave caused by an earthquake

What are the 3 types of seismic waves?

primary, secondary, and surface

What are primary seismic waves?

the fastest waves (5 kilometers per second or approximately 3 miles per second) and can travel through solid, liquids, and gases

What are secondary seismic waves?

travel through Earth’s interior at about half the speed of primary waves. can travel through rock, but unlike primary waves, they cannot travel through liquids or gases

What are surface seismic waves?

move along Earth’s surface, not through its interior. the slowest of the three seismic waves

What are Tsunamis?

giant waves caused by earthquakes or volcanic eruptions under the sea. Out in the depths of the ocean, tsunami waves do not dramatically increase in height. However, as the waves travel inland, they build up to higher and higher heights as the depth of the ocean decreases.

What are Plate tectonics?

the theory that Earth’s outer shell is divided into several plates that glide over the mantle or the rocky inner layer above the core. The plates move and separate, causing Earth to separate and change.

What is soil?

a mixture of minerals, organic matter, gases, liquids, and many organisms that together support life on Earth

What is the water cycle?

also called the hydrologic cycle, is a continuous circulation of water throughout Earth and Earth’s atmosphere

What is transpiration?

when plants suck water from roots to the small pores in leaves, releasing the water vapor into the atmosphere

What are the layers of soil?

bedrock, subsoil, topsoil

How old is the Earth?

4.5 billion years old

What was the Hadean eon?

Earth is formed out of debris around the solar protoplanetary disk. There is no life. Temperatures are extremely hot with frequent volcanic activity. The Moon is formed around this time. 4.5 billion years ago

What was the Archean eon?

Prokaryote life, the first form of life, emerges. The atmosphere is composed of volcanic and greenhouse gases. 2.5 billion years ago

What was the Proterozoic eon?

Eukaryotes, a more complex form of life, emerge, including some forms of multicellular organisms. Bacteria begin producing oxygen, shaping the third and current of Earth’s atmospheres. Plants, animals (later in this time period), and possibly earlier forms of fungi form around this time). 541 million years ago

What was the Phanerozoic eon?

Complex life, including vertebrates, begin to dominate Earth’s ocean. Gradually, life expands to land, and familiar forms of plants, animals, and fungi begin appearing. Animals—including humans—evolve at the most recent phases of this eon. up to present day

What are rocks?

any naturally occurring solid mass or aggregate of minerals or mineraloid matter. are categorized by the minerals they include, their chemical composition, and their formation (origin). are usually grouped into three main categories: igneous, metamorphic, and sedimentary. form the Earth’s outer solid layer: the lithosphere

What are Igneous rocks made of?

lava, magma

What do igneous rocks look like?

glassy, smooth surface, gas bubble holes, random arrangement of minerals

What are some examples of igneous rocks?

granite, pumice, obsidian

What are Metamorphic rocks made of?

heat pressure

What do metamorphic rocks look like?

sparkly crystals, ribbon-like layers

What are some examples of metamorphic rocks?

marble, slate, gneiss

What are Sedimentary rocks made of?

deposition, cementation

What do sedimentary rocks look like?

sand grains or visible pebbles; fossils may be visible

What are some examples of sedimentary rocks?

conglomerate, sandstone, limestone, shale

How are fossils formed?

when organisms are buried by sediments

How far away is the Earth from the Sun?

it is the 3rd planet away

What are some characteristics of Earth?

densest planet in the solar system, largest of the 4 terrestrial planets, only known planet to harbor life