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