Glossary

absorb take in energy, or a fluid substance

acceleration rate of change of velocity; change of velocity in a certain time

accurate close to an expected value

acids substances producing hydrogen ions in solution; substances that produce a solution with pH value less than 7

acoustics the branch of physics concerned with the properties of sound

adaptation a characteristic or trait that helps an organism survive in its habitat '

adapted when an organism or trait has modified or become better suited for its surroundings

air resistance force of resistance produced by the action of air particles on a moving object

alkali substances producing hydroxide ions in solution; substances that produce a solution with pH value greater than 7

alleles teiea alternative forms of a gene alloy a mixture of metals altitude distance above sea level

amplifier any device that increases the amplitude of a signal; electronic device that increases amplitude of electrical signals

amplitude distance from the equilibrium (midpoint) of an oscillation to the point of maximum displacement

aperture an opening or gap through which light passes in an optical instrument

approximation a value that is nearly the same as another, but not exactly correct

aqueous humour the clear fluid filling the space in the front of the eyeball between the lens and the cornea

asexual reproduction reproduction by cloning of a single parent organism, without the combination of genetic information

atomic mass the measured mass of a chemical element expressed in atomic mass units. Approximately equal to the number of protons and neutrons in the nucleus, or to their average number when relative abundancies of isotopes are included

atomic number number of protons in the nucleus of an atom, defining the place of an element in the periodic table

attract action of a force that tends to bring two objects closer together

auditory relating to hearing axis a line of reference for measuring coordinates

balanced equal on both sides

bases building blocks for DNA; either adenine, cytosine, guanine, or thymine

binary fission a type of asexual reproduction that usually occurs in prokaryotes (like bacteria) and other single-celled organisms

blastocyst a group of cells that forms in the early stages of the development of an embryo bonded joined chemically

budding a type of asexual reproduction in which a ‘bud’ or small outgrowth grows off the parent organism before breaking off into an independent organism

calculus mathematical method to express the properties of functions through infinitesimally small differences

calibrating adjusting an instrument or reading to an expected value or to a standard reference point

camera obscura a darkened room with a small aperture to produce a projected image of the outside

central nervous system (CNS) the part of the nervous system that is composed of the brain and spinal cord and is responsible for controlling the functions and actions of the body

centrioles small organelles that help with the production of the spindle fibers for cell division

centromeres the place on a chromosome where the spindle fibers attach during cell division

chemical formula symbolic expression of the atomic composition of a substance

chemical reaction any process where particles are exchanged between reactants to produce products with new chemical properties

chromosome thread-like structures in the nucleus of cells that contain the genetic information for the organism

ciliary muscles muscles that stretch the lens in the eye to change its curvature

climatograph (climograph, climogram) graphic representation of the average monthly temperature and precipitation in a given area during a year

cochlea spiral tube in the inner ear that converts physical vibrations of sound to nerve impulses

coke a fuel made by heating coal to purify it

combustion process of burning something; the rapid exothermic oxidation of a substance

compressions regions of relatively higher pressure

cones in the eye, light sensitive cells that respond to different wavelengths, giving the perception of colour

conservation of mass law stating that mass is never created or destroyed in a chemical process, but only reorganised

coordinates a group of numbers used to indicate a position in a geometric space, such as on a line or plane

core the innermost layer of the Earth cornea transparent tissue that covers the front of the eye crest in a wave, the point of greatest positive displacement

cubitancient length measurement, thought to be equivalent to the length of a man’s forearm

currents air or water that moves in a particular direction datum a single point of information (plural: data) daughter cells the cells that result from cell division

decibel scale scale for measuring the loudness of sound or other signals

decompose in chemistry, to break down a compound to simpler components, or elements

deduced work out a conclusion by logical processes

deuteranopia defect of colour vision caused by insensitivity to green light, resulting in confusion of greens and reds

differentiate the process of cells becoming specialized to make up different tissues and organs and to perform specific functions

dilution reducing concentration of a solution by adding more solvent

displacement moving something from its usual position; in chemistry, the replacement of a compound or substance with another

displacement reaction reaction in which chemical displacement occurs

DNA replication the process of making an exact copy of DNA

dominant the genetic characteristic that appears in the offspring as long as the offspring inherited one allele of the trait from its parents

double helix the shape of a molecule of DNA, in which the two strands that make up the DNA are wound together

durable hardwearing, able to withstand sustained use dye a chemical substance that adds colour ear canal the channel leading from the outer to the middle ear

eardrum the tympanic membrane; thin tissue across the ear canal in the middle ear which vibrates in response to sound waves

egg female gamete (sex cell)

electric field a volume of space in which electrical charges exert forces on other electrical charges

electrolysis chemical decomposition produced by passing an electric current through a liquid or solution containing ions

electromagnetic radiation energy produced by varying electrical and magnetic fields of different frequencies, including visible light, ultraviolet radiation and gamma rays

electromagnetic spectrum the range of electromagnetic fields organised in terms of wavelength and categorised in terms of their effect on matter

electron an elementary particle with a negative electrical charge, usually found outside the nucleus within atoms

elevation height above sea level

emit give out, especially energy or waves

enzymes biological catalysts that speed up chemical reactions in a living organism

epigenetics the non-genetic factors that influence an organism’s characteristics

equilibrium position point of rest for an object or a medium when no resultant force is acting

erosion the process of breaking down or destroying a surface or substance

evolve the process of changing over time fetus unborn offspring of a mammal

focus point of convergence of rays, for example light rays

foot a unit of measurement in the ’British lmperial’ measurement system equal to twelve inches

fovea a small depression in the retina of the eye where visual sensitivity is highest and where retinal cones are particularly

concentrated fragmentation breaking DNA into pieces frequency the number of oscillations per second

friction retarding force resulting from the physical interaction of two objects in physical contact, always acting against the direction of motion gametes male or female sex cells that combine in the process of sexual reproduction

gel electrophoresis laboratory procedure that allows DNA fragments to be separated and visualized according to the molecular size of the fragments gene pool all of the possible genes present in a population

gene a section of DNA that codes for characteristics of the organism; genes are inheritable and passed from parents to offspring

gene expression when the information contained within a gene is observable

genotype the genetic makeup of an organism

genus a taxonomic category, higher than species but lower then family, for example Homo

gland an organ that produces chemical substances, such as hormones

gold leaf very thin sheet of gold gradient slope or incline, especially of a line or curve on a graph gravity attractive force acting between all masses

Greenwich Mean Time a time standard, where midday is defined when the Sun passes its zenith over a meridian through Greenwich in East London, UK groups in the periodic table, elements arranged in a vertical column hand an ancient unit of length, based on the breadth of the palm heterozygous a pair of genes in which one gene is dominant and one gene lS recessrve homozygous when both alleles are matching inch a unit of length in the British Imperial measurement system, equal to 2.54cm

indicator any chemical substance whose change of property can be used to detect the presence of other substances, especially colour changes in the presence of acids and alkalis

inertia the resistance of a mass to any change in its state of motion

inheritable diseases diseases that are passed from parent to offspring through genes

interference effect of combination of two waves to make a resultant wave ion a charged atom, resulting in the gain or loss of electrons iris the coloured part of the eye surrounding the pupil kilogram standard unit of mass in the SI unit system

kingdom largest taxonomic category according to common fundamental characteristics

latitude angular distance of a place north or south of the equator

lava melted rock that erupts from a volcano or crack in the Earth

leeward the side that is sheltered or away from the wind

lens a prism whose shape causes rays to converge or diverge to a point

limestone sedimentary rock formed from the shells of prehistoric sea creatures

limewater a solution of calcium hydroxide

longitude angular distance of a place east or west of the Greenwici Meridian

longitudinal oscillation an oscillation in which the medium moves to and fro in the same axis along which energy is transferred

magma melted rock that is still contained within the Earth matter physical substance that has mass or takes up space

measurement standard a physical reference used to define units of measurement, such as length, mass or time

medium (media) any material through which energy travels in the form of a wave

meiosis type of cell division that results in the production of gametes

metre Systeme Internationale (SI) fundamental unit of length

metric any unit of measurement deriving from the metre in the Systeme Internationale (Sl) standard

microtubules small tube-like structures that are found in the cytoplasm of cells

mitosis cell division

molecule a group of atoms bonded together, representing the smallest fundamental unit of a chemical compound that can take part in a chemical reaction

momentum a quantity related to inertia found by multiplying the mass by the velocity of an object

motor nerves nerves that carry impulses from the central nervous system to muscles

mutated genetic information that has been changed or modified from its original form

native deposits metals found in their metallic form in rock, either elemental (pure) or as an alloy

natural selection the process through which organisms better suited for survival in a habitat give rise to more offspring that are also better suited, and that can eventually lead to evolution of new species

nerves a bundle or group of neurons

neurons nerve cells

neutral devoid of a certain property, for example, without electrical charge, or without acidity or alkilinity

neutron nuclear particle with mass slightly greater than a proton but with no overall electrical charge

nitrogenous base one of the nitrogen containing molecules (adenine, cytosine, guanine, thymine) that make up DNA

nucleus massive central part of an atom, containing protons and neutrons

offspring the young organism that results from reproduction omnivorous living thing that eats both animal and plant matter

optic related to light, and instruments that are used to manipulate light

orbit a closed trajectory (circular or elliptical) around another object, such as a planet or an atomic nucleus

ore a naturally occurring solid material from which a metal or mineral can be extracted

origin in Cartesian coordinates, the point of intersection of axes, from which coordinates are numbered

oscillation any vibration or movement back and forward ossicles tiny bones of the middle ear

outer ear the part of the ear including the pinna or auricle and the auditory canal

oval window aperture at the innermost end of the auditory canal

oxidation reaction a chemical reaction in which oxygen is added to a reactant by addition or displacement

oxide a chemical compound consisting of a metal and oxygen

Pangaea the supercontinent that was made up of all the current continents before the occurrence of continental drift

paradox a seemingly contradictory statement which may nevertheless be true

parthenogenesis reproduction from a female organism even though fertilization has not occurred

PCR polymerase chain reaction laboratory procedure to rapidly make multiple copies of a fragment of DNA

peak in oscillations and waves, the point of maximum positive displacement from equilibrium

periods in the periodic table, elements arranged in a horizontal row

physical properties a property that is measurable, defining the physical or mechanical state of an object

pigment compound that gives colour to an organism or parts of an organism pinna the outer ear visible outside the skull, also called the auricle

pitch the perceived property of a sound wave that relates to frequency

plate tectonic theory the theory that the surface of the Earth is covered by land masses that move slowly over the surface of the Earth

plates land masses that make up the surface of the Earth

polymers a substance whose molecular structure consists of a number of smaller, similar units bonded together

precipitation rain, snow, sleet, or hall that falls to the earth during the water cycle

precise in measurement, results or measurements that are in close agreement with each other (without necessarily being correct)

primary colours a group of colours from which all other colours can be obtained by mixing

prime meridian the line of longitude defined as zero degrees for any planet

prism a transparent object whose shape is used to control light by refraction

products what is produced in a chemical reaction propagation reproduction, or spreading out of an effect or energy

protons nuclear particles with significant mass and carrying a positive electrical charge

pull factors any factor which attracts, particularly for human migration pupil the aperture at the front of the eye through which light passes

push factors any factor which repels, particularly for human migration

quark theoretical elementary particle which in groups form larger, massive particles called hadrons

rain shadow effect when a geographic feature, such as a mountain range, blocks the moist air that leads to precipitation, leading to a relatively dry area

reactants substances that undergo a chemical reaction

reactivity series hierarchy of metals and other elements in terms of their chemical reactivity

recessive the genetic characteristic that appears in the offspring only if the offspring has inherited the same allele of the trait from both of its parents

reduced to have lost oxygen, gained hydrogen or gained electrons through a chemical reaction reflex involuntary muscular response

refraction change of direction of propagation of light or other waves as they pass from one medium to another

relative velocity velocity of an object relative to another moving object

reliable replicable results that can be reproduced in subsequent experiments

resonance constructive interference of vibrations / sound waves to produce much larger vibrations

retina tissue at the back of the eye containing light-sensitive cells rods light-sensitive cells in the eye that respond to brightness only run-off water that drains away, down the surface of the Earth

salt a chemical compound formed by the reaction of an acid with a base (alkali)

seismic relating to movement of the Earth and the Earth's crust seismic activity vibrations caused by movement of tectonic plates

sense organs organs, such as eyes, nose, mouth, ears, and skin, that are capable of perceiving different stimuli

sexual reproduction production of new organisms through the combination of male and female genetic information

sister chromatids the identical strands of genetic information that are produced during the process of mitosis

sonar detection system that uses reflection of sound waves

species taxonomic category of living things that can reproduce together, for example Homo sapiens

sperm male gamete (sex cell)

steel an alloy of iron and carbon

stimulus (stimuli) a substance or event that causes a reaction

subatomic particle any particle smaller than an atom, principally protons, neutrons and electrons

subduction zone boundary of two plates that have collided, when one plate slides under the other

tension a stretching force

time period time taken for one oscillation to complete

time zone range of longitudes on the Earth where the clock time is adjusted to the same value

tissues groups of cells of the same type

topographic graphic representation of the features of the surface of the Earth

topography the features of the surface of the Earth trait characteristic

transverse oscillation oscillation in which the medium is moving at right angles to the direction of propagation of energy

trough in waves, the point of maximum minimum displacement of a medium

ultrasound high frequency sound used for echolocation, especially in medicine

universal indicator a mixture of indicators to provide a colour spectrum relating to the acidity and alkalinity of a solution

vectors arrows indicating direction and magnitude velocity the speed in a certain direction, displacement per unit time

vestibulocochlear nerve also called the auditory nerve, nerve responSIble for transmitting signals from the inner ear to the brain

volume the perceived property of a sound wave related to its amplitude

wavelength the distance from a point in an oscillation to the same point in the next oscillation

weathering the process of erosion that occurs from the exposure to different weather conditions, such as rain and wind

windward the side that is exposed to or in the direction of the wind

word equation representation of chemical reactions using the names of compounds