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 involved bar Non-SI unit of gas pressure

biome A complex ecosystem that is characterized 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 boundaryBoundary 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 substanc 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 1 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 scaleA 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 1 mantle A region inside the Earth consisting of a thick, slow-moving liquid of magnesium, iron and silicates mating The process of sexual reproduction