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abiotic

relating to non-living parts of an environment such as sunlight, soil, moisture, and temperature

acceleration

the rate at which an object changes its velocity

acceleration due to gravity

acceleration due to gravity in the absense of air resistance; the value of acceleration due to gravity near the surface of the Earth is approximately 9.8 m/s2 downward

accuracy

the difference between a measurement and its accepted value

acids

compounds containing hydrogen that produce a solution with a pH of less than 7 when they dissolve in water and that produce a salt and water when they react with ionic compounds containing hydroxide ions

adaptations

characteristics that enable organisms to better survive and reproduce

adaptive radiation

the development of a number of new species from a common ancestor; the new species are adapted to inhabit different niches

aeration

mixing with air; one method to reduce run-off is to mechanically remove small plugs of soil to improve air and water flow through the soil

air mass

a large body of air with similar temperature and humidity throughout its length

air resistance

a friction-like force that opposes the motion of objects that move through the air

albedo

the amount of radiation reflected by a surface

alcohol

one kind of organic compound that contains C, H, and O, such as methanol and ethanol

alpha decay

the process in which an alpha particle is emitted from a nucleus

alpha particle

a positively charged atomic particle that is much more massive than either a beta particle or gamma radiation and is relatively slow moving; has same combination of particles as the nucleus of a helium atom

angle of incidence

the angle between a ray reaching a surface and a line perpendicular to that surface

anions

negative ions

asthenosphere

a partly molten layer in Earth's upper mantle just below the lithosphere

atmospheres

layers of gases that extend above a planet's surface

atmospheric pressure

the pressure exerted by the mass of air above any point on Earth's surface; also called air pressure

atom

the smallest particle of any element that retains the properties of the element

atomic number

the number of protons in the nucleus of an atom, which identifies the element to which the atom belongs

average acceleration

average rate at which an object changes its velocity; shown by the slope of a velocity-time graph

average velocity

the rate of change in position for a time interval

balanced chemical equation

a chemical equation that identifies each pure substance in the equation as well as showing the matching number of atoms of each element on both sides

barometer

an instrument used to measure atmospheric pressure

bases

chemical compounds containing hydroxide that produce a solution with a pH of more than 7 when they dissolve in water, and produce a salt and water when they react with ionic compounds containing positive hydrogen ions

behavioural adaptation

what an organism does to survive in the unique conditions of its environment

best-fit line

a smooth curve or straight line that most closely fits the general shape outlined by the points on a graph; shows the trend of the data. Also called the line of best fit

beta decay

the process in which a neutron changes into a proton, which remains in the nucleus, and an electron, which is emitted from the nucleus along with energy

beta particle

a high speed electron; emitted by a radioactive nucleus in beta decay

binary covalent compound

a compound that consists of two nonmetallic elements joined together by one or more covalent bonds

bioaccumulation

the gradual build-up of synthetic and organic chemicals in living organisms

biodegredation

the breaking down of dead organic matter by living organisms such as bacteria

biodiversity

the diversity of plant, animal life and micro-organisms in a particular habitat (or in the world as a whole)

biogeoclimatic zone

a region with a certain type of plant life, soil, geography and climate

biomagnification

the process in which chemicals not only accumulate but become more concentrated at each trophic level in a food pyramid

biomass

the total mass of living matter in a given unit area

biome

the largest division of the biosphere, which includes large regions with similar biotic components and similar abiotic components

bioremediation

the act of treating waste or pollutants by the use of microorganisms (as bacteria) or plants that can break down the undesirable substances such as chemical pollutants to reverse or lessen environmental damage

biosphere

the thin layer of air, land and water on or near Earth's surface in which all living things on Earth exist

biotic

relating to living organisms such as plants, animals, fungi and bacteria

bohr diagram

a diagram that shows the arrangement of an element's subatomic particles and the number of electrons in each shell surrounding the nucleus of an atom

bonding pair

a pair of electrons involved in a covalent bond

bromothymol blue

an acid-base indicator names after its colour change from yellow to blue over a pH range of 6-7.6

carbon cycle

the nutrient cycle in which carbon is moved through the biosphere; maintains the balance of CO2 in the atmosphere

carbon offset

an emission-reduction credit that people buy to help make up for their greenhouse gas emissions

carbon sink

a body or process (e.g., plants, oceans, and soil) that removes carbon dioxide from the atmosphere and stores it

carbon source

a body or process (e.g., burning fossil fuels or trees) that releases carbon dioxide into the atmosphere

carbonate

a combination of carbon and oxygen that os dissolved in ocean water

carnivores

secondary consumers that eat primary consumers and often other secondary consumers. They are often at the tertiary level of a food chain; also known as top carnivores

catalyst

a substance that speeds up the rate of a chemical reaction without being changed or used up itself

catalytic converter

a stainless steel pollution-control device, shaped like a muffler and located under the frame of a vehicle; converts poisonous gases from the vehicle's exhaust into less harmful substances

catastrophic events

large scale disasters

cations

positive ions

caustic

harsh; describes solutions made from highly reactive bases, such as drain cleaner and oven cleaner

cellular respiration

the process in which both plants and animals release carbon dioxide back into the atmosphere by converting carbohydrates and oxygen into carbon dioxide and water

chain reaction

an ongoing process in which one fission reaction initiates the next reaction

change in velocity

change that occurs when the speed of an object changes, or its direction of motion changes, or both; calculated by subtracting the initial velocity from the final velocity

chemical changes

changes in how the atoms and molecules in a pure substance are arranged and interconnected

chemical equation

the representation of a chemical reaction in words or symbols

chemical reaction

one more more chemical changes that occur at the same time

climate

the average conditions of the atmosphere. for example precipitation, temperature and humidity in a large region over 30 years of more

climate change

changes in long-term weather patterns in certain regions

climatograph

a graph of climate data for a specific region; the data are usually obtained over 30 years from local weather observation stations

climax community

a mature community, such as a boreal forest, tropical rainforest, grassland, or desert, that continues to change over time

closed system

a system that does not exchange matter with its surroundings, although energy in the form of radiation can leave or enter the system

coefficients

numbers placed in front of a chemical formula or a chemical symbol for an element that show the ratios between the various compounds in a chemical reaction

combustion

the rapid reaction of a compound or element with oxygen to form an oxide and to produce heat

commensalism

a symbiotic relationship in which one species benefits and the other species is neither helped nor harmed

community

all the populations of the different species that interact in a specific area or ecosystem

competition

a harmful interaction between two or more organisms that can occur when organisms compete for the same resource in the same location at the same time

composite volcano

a large, cone-shaped volcanic mountain; the cone shape is the result of repeated eruptions of ash and lava

compound

a pure substance that is composed of two or more atoms chemically combined in a specific way

concentration

the amount of substance dissolved in a given volume of solution- for example, the number of hydrogen ions in a specific volume of solution

conclusion

the explanation of the results of an experiment as it applies to the hypothesis being tested

conduction

the transfer of thermal energy from one substance to another or within a solid by direct contact of particles

conservation of mass

the preservation of mass in a chemical reaction; the total mass of the products is always equal to the total mass of the reactants

constant acceleration

velocity changing at a constant rate

consumer

an organism that eats other organisms

contamination

the introduction of chemicals, toxins, wastes, or micro-organisms into the environment in concentrations that are harmful to living things

continental drift theory

the theory that the continents have not always been in their present locations but have moved there over millions of years

convection

the transfer of thermal energy within a fluid and with the movement of fluid from one place to another

convection current

the movement of a fluid caused by density differences

convergent plate boundary

a region where tectonic plates are colliding

convergent plates

tectonic plates that are colliding

coriolis effect

a change in the direction of moving air, water, or objects due to Earth's rotation

correlation

a mutual relation between two or more things

corrosive

biting; describes some acids and bases that can burn or eat away many materials, such as metals and human tissue

covalent bonding

the formation of a chemical bond between atoms through the sharing of one or more pairs of electrons

covalent compound

a compound formed when non-metallic atoms share electrons to form covalent bonds

crust

Earth's outermost layer formed by lighter materials, such as silicon and oxygen, floating to the top during Earth's early cooling period

daughter isotope

the stable product of radioactive decay

DDT

an insecticide and well-known persistent organic pollutant, now banned in many countries

decay curve

a curved line on a graph that shows the rate at which radioisotopes

deceleration

acceleration that is opposite to the direction of motion; a decrease in the speed of an object

decomposers

organisms that break down wastes and dead organisms and change them into usable nutrients available to other organisms

decomposition

in biology, the breaking down of organic wastes and dead organisms; in chemistry, a chemical reaction in which a compound is broken down into two or more elements or simpler compounds

deforestation

the clearing or logging of forests without replanting

denitrification

the process in which nitrogen is returned to the atmosphere

denitrifying bacteria

bacteria that convert nitrate back into nitrogen gas

dependent variable

in an experiment, the factor that changes in response to a change in the independent variable; also called the responding variable

detrivores

consumers that feed at every trophic level, obtaining their energy and nutrients by eating dead organic matter

dew point

the temperature at which water vapour condenses

diatomic molecule

a pair of atoms of the same element that are joined by covalent bonds

displacement

the straight-line distance and direction from one point to another

distance

a scalar quantity that describes the length of a path between two points or locations

divergent plate boundary

a region where tectonic plates are spreading apart

diverging plates

tectonic plates that are spreading apart

double replacement

AB + CD --- AC + BD

earthquake

a sudden, ground shaking release of built-up energy at or under Earth's surface

ecological hierarchy

the order of biotic interactions and relationships in an ecosystem: organism, population, community, ecosystem

ecological pyramid

a food pyramid. There are three types of ecological pyramids: pyramid of biomass, pyramid of numbers, and pyramid of energy

ecological succession

changes that take place over time in the types of organisms that live in an area

ecosystem

a part of a biome in which abiotic components interact with biotic components

El Nino

an unusually warm ocean current that develops periodically off the coast of Ecuador and Peru, often producing unusually mild weather along the coast of British Columbia and in eastern Canada

El Nino-Southern Oscillation

a system of ocean and atmosphere changes in the tropical Pacific region, including El Nino and La Nina events

electromagnetic radiation

the transfer of energy by waves travelling outward in all directions from a source

electrons

subatomic particles that have a 1- (negative) electric charge

elevation

the height of a land mass above sea level

energy flow

the flow of energy from an ecosystem to an organism and from one organism to another

enhanced greenhouse effect

the increased capacity of the atmosphere to trap thermal energy because of an increase in greenhouse gases

epicentre

the point on Earth's surface directly above the focus where an earthquake starts

estimating

making an informed judgement about a measurement

eutrophication

process by which a body of water becomes too rich in dissolved nutrients, leading to plant growth that depletes oxygen

exosphere

the fifth layer of Earth's atmosphere

extinction

the dying out of a species; species become extinct when their numbers are reduced to zero

fair test

A controlled experiment where one variable is changed and all others (to the extent possible) are held constant.

faults

large breaks in rock layers

fission

a nucleur reaction in which a large nucleus breaks apart, producing two or more smaller nuclei, subatomic particles, and energy

fluids

substances in which the particles can flow freely

focus

in geology, the location inside Earth where an earthquake starts

food chain

a model that shows the flow of energy from plant to animal and from animal to animal

food pyramid

a model that shows the loss of energy from one trophic level to another; often called an ecological pyramid

food web

a model of the feeding relationships within an ecosystem; formed from interconnected food chains

force

a push or pull that acts on an object

foreign species

introduced species

front

the boundary between two air masses

fusion

a process in which two low mass nuclei join together to make a more massive nucleus

gamma decay

a process in which an isotope falls from a high energy state to a lower energy state, giving off a high energy gamma ray; the result of a redistribution of energy within the nucleus

gamma radiation

rays of high-energy, short-wavelength radiation emitted from the nuclei of atoms

General Circulation Models

computer models designed to study climate

geologic uplift

the process of mountain building in which Earth's crust folds and deeply buried rock layers rise and are exposed

global warming

the increase in global average temperature

global warming potential

the ability of a substance to warm the atmosphere by trapping thermal energy

gravity

attractive force between two or more masses; causes objects to be pulled toward the centre of Earth

greenhouse gases

gases in Earth's atmosphere that absorb and trap radiation as thermal energy

habitat

the place in which an organism lives

habitat fragmentation

splitting of ecosystems into small fragments

habitat loss

the destruction of habitats that usually results from human activites

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