Glossary
abiotic The non-living components of an ecosystem
absorb Process by which a liquid is taken up or physically trapped within the structure of a solid
adaptations Changes in the structures or functions of an organism that make it better suited to survive in its environment
altitude Height above sea level on Earth, or ground level elsewhere
analytical To take an object or idea apart and examine its components or pieces to see how they work
apparatus Any equipment used in a scientific experiment aquifer Liquid water held in rocks under the ground
archaeologist A scientist and historian who uses evidence from relics found in the Earth to learn about the past
artificial material A material that has been manipulated or created by humans
asexual reproduction Reproduction that occurs Without the combination of male and female genetic information; only one ‘parent' organism is invoked
bar Non-SI unit of gas pressure
biome A complex ecosystem that is charactenzed by climate and the plants and animals that live there
biotic The living components of an ecosystem
biotic change A change caused by the action of living organisms
bonds Joints or connections between atoms
capillary action The ability of liquids to move through a thin tube without external force due to the action of forces of adhesion and surface tension
cellular respiration A chemical process that occurs inside the cells of all living things. and which produces energy for the cells and organism to survive
chemical change A change resulting in a new chemical substance
chemical neutralization A reaction between an acidic and a basic substance that results in neutral products
chemical reaction Process by which two substances or reactants undergo chemical change to form new substances or products
chromatography Separation process that utilizes the different solubilities of liquids in different solvents
clone A cell or organism that has the same genetic information as another one
combustion Burning, or the rapid oxidation of a substance, producing heat
competition The struggle between different organisms over the same resources
compress To put under pressure
conduction Process by which energy is transferred through contact between particles, by vibration or translation, such as heat, sound or electricity
conservation of energy The principle that energy cannot be created or destroyed, only transferred from one form to another
constructive boundary Boundary between tectonic plates that are moving apart, such that magma is forced to the surface to make new rock
controlled variable A variable that is expected to be affected by the independent variable, but whose effect is not being investigated, so it is kept constant
convection Process by which energy is transferred through the bulk motion of particles
core The centre of the Earth, around 3000 km beneath the surface, consisting largely of iron and nickel
crust Thin, rocky layer on the surface of the Earth
crystal A solid substance that has a regular geometrical physical structure
decomposer An organism, such as bacteria or mushrooms, that breaks down dead organisms into smaller, more simple substances
decomposition Chemical breakdown of a substance by living organisms; rotting or decay (see also fermentation)
density The mass of a substance per unit volume
dependent variable A variable that is expected to be affected by the independent variable, usually measured
destructive boundary Boundary between tectonic plates that are moving together, such that rock is forced down beneath the surface
diameter Line splitting a circle into two semicircles diet The food eaten by an organism
dissolve Process whereby the particles of one substance are physically trapped Within the structure of another, without chemical bonding
distillation Process of evaporating then condensing a liquid, such that all dissolved substances are removed or separated
distilled water Water that has been evaporated and condensed to remove all dissolved impurities
DNA Deoxyribonucleic acid; a large molecule inside each cell that has the genetic information for the characteristics of the organism
ecological footprint A measurement of the effects that people have on the natural balance in ecosystems around the world
ecosystem Different populations that interact with biotic and abiotic factors in their shared habitat
environmental impact evaluation Assessment or evaluation of the effect of our actions on the living or non-living environment
eon The longest geological time period: billions of years, comprising geological eras
era The second longest geological time period: many millions of years
erode The gradual wearing away of rock by natural processes
evolution A change in the genetic and physical characteristics of a species over many generations
experiment A procedure carried out under controlled conditions to provide observations that will test a hypothesis or demonstrate something known or new
fermentation Chemical breakdown of a substance by living organisms to give new chemical substances, such as alcohols (see also decomposition)
filtration Process of removing particulates from a suspension
fixed point A physical change that is used to specify a particular point on a temperature scale
fossil fuel A substance formed in the ground that has energy stored in its chemical bonds, such as coal, oil or natural gas
gas A physical state of matter where particles are arranged and only very weakly bonded, or not bonded at all, so that the material fills a containing volume
genetic information The molecules in a cell (DNA) that direct the functions and characteristics of the cell and the organism
glacier Large mass of ice on the land
gravity Force of attraction between any two masses; a fundamental force of nature
habitat The environment or surroundings where an organism lives
harness To use to do work
heat Thermal energy that is transferred between regions at different temperature
helium The second lightest element (hydrogen is the lightest)
herbivory The process of eating plants
homeostasis The tendency of an organism to maintain itself in a stable, healthy balance
hydrological cycle Process by which water is recycled in the Earth’s environment
independent variable The variable that is changed under controlled conditions
infra-red radiation Energy transferred as a wave with wavelength a little longer than that of visible red light
ingest To swallow or take a substance into the body
inheritable A characteristic or trait that is able to be passed to new generations through DNA and the process of reproduction
insulator A poor conductor of heat kinetic energy Energy due to physical motion
kingdom A large category of living things, for example plants, animals, bacteria and fungi
lava Molten rock
limestone Sedimentary rock formed by the compression of the shells of prehistoric sea creatures
linear scale A scale that increases by unit amounts, as in a straight line
liquid A physical state of matter where particles are arranged and weakly bonded so that the material remains in one piece but can flow
magma A mixture of molten (melted) and semi-molten rock found beneath the surface of the Earth
magnetic field A region of space where magnetic forces can be detected
mantle A region inside the Earth consisting of a thick, slow-moving liquid of magnesium, iron and silicates
mating The process of sexual reproduction
mesocosm An experimental system that models an ecosystem
mesosphere Region of the Earth's atmosphere above the stratosphere, extending to around 80 km of altitude
metabolic process Process in an organism that supports life metabolism The chemical reactions that occur in the cells of living things to process molecules and produce energy for the organism
methodical To follow a procedure carefully
microscopic Requiring a microscope or other magnifying device to see typically less than a millimetre in size
model A representation of a natural phenomenon so that it can be studied and understood
mutualistic A relationship between different species in which all the species benefit
natural material A material found in its raw form in nature
non-linear scale A scale that increases by multiple or exponential amounts
nuclear fusion Process by which the nuclei of two lighter elements come together to form a bigger nucleus, releasing energy and radiation
nutrients Substances that living things use to construct important molecules necessary for survival
observation Something seen; in science, something seen (observed) under controlled conditions
offspring The child or product of reproduction
orbit A circular or elliptical path of one object around another
organism A living thing
oxidation Chemical change in which oxygen reacts and bonds with another substance
ozone layer Region of the Earth’s atmosphere in which ultra-violet radiation from the Sun is filtered by the molecule ozone, O3
palaeontology The study of the prehistoric, particularly of fossils
parasitic A relationship between different species in which one of the species benefits and the other species is harmed
pascal (Pa) Unit of pressure in the 5! system of units
photosynthesis The process of converting solar energy into chemical energy
physical change A change in the arrangement of particles without forming a new substance
physical property The measured physical characteristics of a material
plane A flat surface
population The number of individuals in a species living in the same area at the same time
potential energy Stored energy
predation The process of a consumer hunting, killing and eating another animal
predator An animal that hunts, kills and eats other animals (prey)
prediction Statement about the effect expected to be observed in an experiment
pressure The amount of force per unit area exerted on an object
prey An animal that is hunted, killed and eaten by another animal (predator)
primary consumer An animal that eats plants
producers Plants
propagate Transmission of energy through a medium (substance); spreading of something
prototype The first working model of a machine or other design, used to test it
P-wave A vibration in the Earth causing a compression or side-to-side motion
radioactive dating Use of the decline in radioactivity of natural substances to find their age
radioactivity Natural process where materials give out ionising radiation or particles
rational To be logical, basing deductions and conclusions on what is known with some certainty
resilient Able to recover from stress or damage
retrograde rotation Rotation of a planet or satellite in the opposite direction to its orbit around the Sun
saline A salt solution sandstone Sedimentary rock formed by compressed sand
satellite Any object caught in orbit in the gravitational field of a more massive object
saturated A solution that has absorbed the maximum possible amount of solute
secondary consumer An animal that eats primary consumers
seismometer Device for measuring vibrations in the Earth
sexual reproduction Reproduction that occurs as a result of the combination of male and female genetic information; two ’parent’ organisms are involved
Solar System The system of objects whose motion is strongly determined by the gravitational pull of the Sun
solid A physical state of matter where particles are arranged and strongly bonded so that the material is rigid solubility The extent to which a solute will dissolve in a solvent solute A substance which can be dissolved in a solvent
solution A solute dissolved in a solvent
solvent A substance (usually a liquid) which can dissolve another substance
space probe An artificial device or robot sent by humans to make measurements and observations in space
species A group of living things that have very similar genetic characteristics and can reproduce to have offspring that are also capable of reproducing
spreadsheet A computer program designed to facilitate calculations
state of matter The physical arrangement of matter as solid, liquid, gas or plasma
stimulus (plural stimuli) Something that causes a response in a living thing
stratosphere Region of the Earth’s atmosphere above the troposphere, extending to about 50km of altitude
suspension A mixture of a solid in a liquid that with time separates out on its own
thermosphere Region of the Earth’s atmosphere with very low density but very high particle energies, extending from the stratosphere out to 500 km or more from the Earth’s surface
troposphere Region of the Earth’s atmosphere closest to the surface, between 9km and 17 km in altitude
ultra-violet radiation Energy transferred as a wave with wavelength somewhat shorter than visible violet light
uniform The same throughout
unit of measurement A quantity of measurement, standardized in the metric Systéme international d’unités
or SI units valid Relevant to the inquiry; reasonable
variable Any quantity that can change or be changed in an experiment
viable Whether or not a process or action is economically worthwhile, i.e. can produce a profit
vibrate To move from back and forth around a fixed point