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natural resources

natural materials that are used by humans; they can be classified as renewable or nonrenewable.

pollution

an undesirable change in the natural environment that is caused by the introduction of substances that are harmful to living organisms or by excessive wastes, heat, noise, or radiation.

sustainability

the condition in which human needs are met in such a way that a human population can survive indefinitely.

extinction

the process of ceasing or causing something (species, population) to cease to exist.

nonrenewable resources

resources that form at a much slower rate than the rate that it is consumed.

ecology

the study of the interactions of living organisms with one another and with their environment.

hunter-gatherers

people who obtained food by collecting plants and by hunting wild animals or scavenging their remains.

agricultural revolution

a time period which involved the practice of growing, breeding, and caring for plants and animals that are used for food, clothing, housing, transportation, and other purposes that had a dramatic impact on human societies and their environment.

developing countries

countries that have lower average incomes, simple and agriculture-based economies, and rapid population growth.

non-biodegradable

cannot be broken down by biological processes.

environmental science

the study of the air, water, and land surrounding an organism or a community; it includes the study of the impact of humans on the environment.

biodiversity

the number of different species in a given area.

biology

the study of living organisms.

ecological footprint

a calculation that shows the productive area of Earth needed to support one person in a particular country.

law of supply and demand

a law of economics that states that as the demand for a good or service increases, the value of the good or service also increases.

biodegradable

can be broken down by biological processes.

developed countries

countries that have higher average incomes, slower population growth, diverse industrial economies, and stronger social support systems.

industrial revolution

a time period which involved a shift from energy sources such as animal muscle and running water to fossil fuels, such as coal and oil.

renewable resource

a resource that can be replaced relatively quickly by natural processes.

resource depletion

when a large fraction of a resource is being used up.

probability

the chance that an event will happen.

prediction

a logical statement about what will happen.

data

information gathered during an experiment, often in numeric form.

sample

a group of individuals or events selected to represent the population.

mathematical model

this model includes one or more equations that represents the way a system or process works.

values

principles or standards we consider important.

correlation

association between two or more events; what scientists use to test a prediction when an experiment is unethical or impossible.

risk

probability of an unwanted outcome.

decision-making model

systematic process for making decisions.

experimental method

a series of steps that scientists worldwide use to identify and answer questions.

conceptual model

this model is a verbal or graphical explanation of how a system works or is organized.

bar graph

A diagram in which the numerical values of variables are represented by the height or length of lines or rectangles of equal width.

experiment

A procedure that is carried out under controlled conditions to discover, demonstrate, or test a fact, theory, or general truth.

skepticism

Not believing everything you're told. Being open minded about how the world works and being open to new ideas.

experimental group

The group that receives the experimental treatment.

graphical model

maps and charts are the most common examples of this model.

statistical population

a group of similar things that a scientist is interested in learning about.

observation

is a piece of information we gather using our senses - our sight, hearing, smell, and touch.

consequence

the result of an action.

control group

the group that does not receive the experimental treatment.

gather information

the first step in the decision-making model.

hypothesis

is a testable idea or explanation that leads to a scientific investigation.

physical layers

the division of the Earth into different layers based on their physical properties.

crust

Earth's thinnest layer, composed almost entirely of light elements, makes up less than 1% of the Earth's mass.

seismic waves

the waves that travel through Earth's interior during an earthquake.

tectonic plates

the pieces of lithosphere that are divided and glide across the underlying asthenosphere.

erosion

the removal and transport of surface material.

earthquake

a vibration of the Earth's crust caused by slippage along a fault.

sunlight

visible light that is radiated by the sun.

oxygen

the life-sustaining gas that constitutes 21% of the Earth's atmosphere.

ozone

a molecule made of three oxygen atoms.

convection

transfer of heat through air or water currents.

greenhouse gases

gases in our atmosphere that trap and radiate heat.

ion

an atom or molecule with a net electric charge due to the loss or gain of one or more electrons.

conduction

flow of heat from a warmer object to a colder object.

water cycle

the cycle of processes by which water circulates, driven by the sun.

world ocean

the interconnected system of Earth's oceans.

tributary

A river or stream flowing into a larger river or lake.

evaporation

the change of state from a liquid to a gas.

gravity

The force that attracts a body toward the center of the earth, or toward any other physical body having mass.

surface currents

wind-driven water currents, resulting from global wind patterns.

salinity

a measure of the amount of dissolved salts in a given amount of liquid.

condensation

water vapor forms water droplets on dust particles.

recharge zone

area of the Earth's surface from which water percolates down into an aquifer.

open system

both matter and energy are exchanged between a system and the surrounding environment.

Big Bang Theory

theory that states all matter and energy were once compressed into a single point, 13.7 billion years ago, and expanded to form our universe.

singularity

the single point from which all matter, energy, space, and time expanded.

red shift

a shift in the light spectra of very distant galaxies toward longer wavelengths (toward the red end of the spectrum); generally interpreted as evidence that the universe is expanding.

cosmic background radiation

the radiation emitted from the Big Bang that is left behind by the expansion of the Universe. Its detectable today as radio-wavelength radiation, and we can see it on a fuzzy channel of our TV screens.

light elements

elements (hydrogen, helium, lithium) that were formed during the first million years of our Universe, and continue to be formed through nucleosynthesis.

heavy elements

elements (heavier than Iron (Fe)) that continue to be formed through supernovas, and death of large stars via nucleosynthesis

nucleosynthesis

the cosmic formation of atoms more complex than the hydrogen atom.

nuclear fusion

the process by which nuclei of small atoms combine to form a new, more massive nucleus thereby releasing energy.

galaxy

a system of millions of billions of stars, together with gas and dust, held together by gravitational attraction.

nebular theory

the theory that explains how solar systems are created from nebulae, going through the protostar/protoplanet phase, and ending up with a main sequence star orbited by planets and other bodies.

solar system

the sun and the collection of planets and moons, and other bodies that orbit the sun.

nebula

a large cloud of gas and dust in space, balanced by forces of gravity and pressure.

protostar

a high-temperature, disk-shaped cloud of gas and dust in space that has grown from a nebula to near the point of beginning nuclear fusion and becoming a star.

main sequence

the main cycle of a star's life, undergoing nuclear fusion, with gravity and pressure in a delicate balance.

red giant

a small star that has cooled down, swollen, and turned red.

star death

when a star runs out of hydrogen and helium.

red supergiant

a large star that has cooled down, swollen, and turned red.

white dwarf

a red giant that has run out of fuel and collapsed under its own gravity.

black dwarf

a white dwarf that no long emits heat or light.

neutron star

the remaining core of supernova star once the dust and gas have been released.

supernova

the result of a red supergiant shrinking and exploding that releases massive amounts of energy, dust and gas.

black hole

a region of space with an intense gravitational field when a large star dies.

second generation star

a star produced from supernovas of previous stars, as evidenced by presence of heavier elements.

planetesimal

a small body that orbits the sun, collecting dust and gas, to become a larger planetary body.

planet

a celestial body moving in an elliptical orbit around a star.

basalt

Most oceanic land is composed of ______ rock.

granite

Most continental land masses is composed of ______ rock.

oceanic lithosphere

lithosphere that is mainly comprised of basalt; it is more dense that is why it sits lower in the asthenosphere.

continental lithosphere

lithosphere that is mainly comprised of granite; not as dense as basalt that's why it sits higher up in the asthenosphere.

big burp

the time period when volcanic eruptions went on continuously, releasing gases such as water vapor, carbon dioxide, and sulfur, forming our early atmosphere.

volcanic gases

gases emitted include water vapor, carbon dioxide, and sulfur gases.

early atmosphere formation

formation of the early envelope of gases around the earth, composed of carbon dioxide, water vapor, sulfur gases.

early ocean formation

formation of the early water bodies around the Earth, created by water vapor that cooled enough to condense and precipitate onto Earth.

early life formation

thought to have begun in the oceans, evolved in the absence of oxygen as simple structured bacteria.

stromatolites

layered form of rock formed in shallow water by the trapping, binding and cementation of cyanobacteria, which show some of the most ancient records of life on Earth.

Theia

Earth's twin, theorized to have crashed into Earth, increasing its mass, and remnants forming the Earth's Moon.

Moon

the natural satellite of Earth, formed by leftover matter from Theia.

statistics

the collection and classification of data that are in the form of numbers.

distribution

the relative arrangement of the members of a statistical population; usually shown in a graph.

mean

the number obtained by adding up the data for a given characteristic and dividing this sum by the number of individuals.

variable

a factor that changes in an experiment in order to test a hypothesis.

agriculture

the raising of crops and livestock for food or for other products that are useful to humans.

geosphere

the mostly solid, rocky part of Earth; extends from the center of the core to the surface of the crust.

lithosphere

the solid, outer layer of the Earth that consists of the crust and the rigid upper part of the mantle.

asthenosphere

the solid, plastic layer of the mantle beneath the lithosphere; made of mantle rock that flows very slowly, which allows tectonic plates to move on top of it.

mantle

in Earth science, the layer of rock between the Earth's crust and core.

core

the central part of the Earth below the mantle; also the center of the sun.

model

a pattern, plan, representation, or description designed to show the structure or workings of an object, system, or concept.

atmosphere

A mixture of gases that surrounds a planet, such as Earth.

troposphere

The lowest layer of the atmosphere, in which temperature drops at a constant rate as altitude increases; the part of the atmosphere where weather conditions exist.

stratosphere

The layer of the atmosphere that lies between the troposphere and the mesosphere and in which temperature increases as altitude increases; contains the ozone layer.

radiation

The energy that is transferred as electromagnetic waves, such as visible light and infrared waves.

greenhouse effect

The warming of the surface and lower atmosphere of Earth that occurs when carbon dioxide, water vapor, and other gases in the air absorb and reradiate infrared radiation.

precipitation

Any form of water that falls to the Earth's surface from the clouds; includes rain, snow, sleet, and hail.

fresh water

Water that contains insignificant amounts of salts, as in rivers and lakes.

biosphere

the narrow layer around Earth's surface in which life can exist.

fossil fuel

a nonrenewable energy resource formed from the remains of organisms that lived long ago; examples include oil, coal, and natural gas.

electric generator

a device that converts mechanical energy into electrical energy.

petroleum

oil that is pumped from the ground is also known as crude oil.

oil reserves

oil deposits that can be extracted profitably at current prices using current technology.

nuclear energy

the energy released by a fission or fusion reaction; the binding energy of the atomic nucleus.

nuclear fusion

The process by which nuclei of small atoms combine to form a new, more massive nucleus; the process releases energy.

nuclear fission

The process by which the nucleus of a heavy atom splits into two or more fragments; the process releases neutrons and energy.

closed system

Energy enters and leaves the system, but matter does not.

renewable energy

energy from sources that are constantly being formed.

passive solar heating

uses the sun's energy to heat something directly.

active solar heating

energy from the sun can be gathered by collectors and used to heat water or to heat a building.

biofuel

plant material, manure, or any other organic matter that is used as an energy source.

hydroelectric energy

electrical energy produced by the flow of water.

geothermal energy

the energy produced by heat within Earth's crust.

alternative energy

energy that does not come from fossil fuels and that is still in development.

OTEC

when warm surface water is used to boil cold deep sea water, this is possible because deep sea water boils easily. This proses creates steam to turn a turbine and generate electricity.

hydrogen fuel cell

produces electricity chemically, by combining hydrogen fuel with oxygen from the air. When hydrogen and oxygen are combined, electrical energy is produced and water is the only byproduct.

energy efficiency

the percentage of energy put into a system that does useful work. It can be determined using this simple equation: energy efficiency (in %) = useful energy out/energy in X 100.

energy conservation

is saving energy. It can occur in many ways, including using energy-efficient devices and wasting less energy.

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