V2.34
Words
used in
Science
Words suitable for pupils taking the Science 13+ Common Entrance exam
Name________________________________
ABDOMEN
The last part of an insect’s body (after the head and the thorax). It is the
part that contains the digestive and reproductive organs. In a human it is
the soft part under your lungs (where your intestines and are).
ABSORBENT
Absorbent means ‘soaks up water’. A towel will be absorbent.
ABSORPTION
When light hits an object and does not get reflected back (eg when light hits a
piece of black paper it is absorbed, this is why the paper looks black)
ACID
A liquid with a pH value less than pH 7
Acids: i.
usually sour to taste (do NOT taste anything in the lab.)
ii.
will neutralise an alkali.
iii.
turn BLUE litmus indicator RED
examples of some acids: lemon juice (citric acid), vinegar (acetic acid),
hydrochloric acid (found in your stomach) and sulphuric acid (found in car
batteries).
Acids are often corrosive which means they will attack and eat into substances
such as acid and skin.
ACID RAIN
Rain water which has dissolved gases from the air and become acid is called
ACID RAIN. Gases which cause acid rain include sulphur dioxide (formed when
fossil fuels like coal and oil are burnt) and nitrogen dioxide (comes from car
exhausts).
NOTE: all rain water is slightly acid due to carbon dioxide which is naturally
present in the air.
ADAPTION
In order to help them survive, animals and plants have developed special features
to help them fit into their habitat. These special features are called adaptions
(examples: Fish have a streamlined body to help them move through the water,
camels have large feet to stop them sinking into the sand, Frogs have webbed
feet to help them swim.
AIR
Air is the mixture of gases that surround the Earth. Air consists of nitrogen (about
78%), oxygen (about 21%), argon (about 1%) and a variety of other gases
(including carbon dioxide, helium and water vapour).
Uses for air: Supports Gliders, planes and parachutes. Needed for things to burn.
Kites. Blows sailing boats along.
Air does have weight. There is no air on the Moon
AIR PRESSURE
It is the moving particles continuously colliding against the edge of a container that
causes the pressure in a gas. How to increase the pressure:
i)
By squashing the particles closer together (eg pumping up a tyre or
blowing up a balloon)
ii)
By warming the gas. This makes the particles vibrate faster (this is why a
balloon expands when heated)
(See ATMOSPHERIC PRESSRE)
AIR RESISTANCE
Air resistance happens when air tries to slow down a moving object (like a
parachute or car). Another name for air resistance is drag. It is a kind of friction.
A streamlined object has only a little air resistance.
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ALGAE
Single celled plants. Reproduce asexually by binary fission. Live in wet places.
Have no leaves or roots.
ALIMENTARY CANAL (gut)
The tube that links the mouth to the anus down which food travels.
ALKALI
A liquid with a pH value greater than 7
Alkalis: i.
feel soapy to touch
ii. will neutralise an alkali
iii. turn RED litmus indicator BLUE
examples: washing soda (sodium carbonate), caustic soda (sodium hydroxide),
ammonia soln., garden lime (calcium hydroxide), indigestion mixture (eg
magnesium hydroxide).
Alkalis are caustic and can burn your skin.
Alkali in your eyes is particularly dangerous.
ALUMINIUM
Aluminium is very light metal. It is used to make kitchen foil, saucepans and
sometimes good quality bicycle frames). Aluminium is a good conductor of
heat and electricity.
AMMETER
An instrument used for measuring current. It is placed in series with the conductor
being tested and has a very LOW resistance.
AMNION
A water filled sac (containing AMNIOTIC FLUID) that helps support and protect
the developing embryo.
AMPHIBIANS
One of the VERTEBRATES. An animal that lays soft jelly covered eggs in water.
Have smooth moist skin. Adults live on land or in water. Young live in water and
go through metamorphosis. e.g. frog.
AMPLITUDE
The size of a wave. The amplitude of a sound wave determines what its VOLUME
will be.
ANNELIDS
Segmented worms with bristles on each segment e.g. earthworm or leach.
ANTAGONISTIC MUSCLES Antagonistic muscles are muscles that work in pairs. An example of
antagonistic muscles are the biceps and triceps. The biceps lift the arm up and
triceps pull it down. When the biceps contract the triceps relax and visa versa,
ANTHER
Male part of a flower. Where pollen is made.
ARACHNIDS
Animals that have 4 pairs of legs, 2 parts to the body eg spider, scorpion.
ARTERIES
Carry blood away from the heart.
ARTHROPODS
Animals that have many pairs of jointed legs and an exoskeleton. The arthropods
are divided into several smaller groups eg insects, arachnids and crustaceans.
Examples: woodlouse, spider, fly.
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ASEXUAL REPRODUCTION
A form of reproduction where NO fertilization required. Examples of asexual
reproduction:
i)
Production of spores in non-flowering plants eg moss, and fungi.
ii)
Budding eg in cactus III) runners eg in the strawberry)
iv)
Tubers eg in potato).
v)
Binary fission in single cells eg in amoeba (a single-celled animal) or in
algae (single-celled plants).
The way all individual cells multiply. Disadvantage: daughter cells identical
to parent cells. Advantage: A quick process. Rapid colonisation.
ATOM
The smallest possible part of any substance. Some substances only have one
kind of atom and these are called elements.
Compounds consist of at least two different kinds of atom.
The smallest atom is a hydrogen atom.
BACTERIA
Bacteria are microscopic organisms that can be found anywhere. Some bacteria
are helpful like those found in the soil that make things rot or the bacteria used to
turn milk into yogurt. Some are harmful and can make us ill, causing stomach
upset or a sore throat. (See micro-organism).
BALANCED DIET Our diet is what we eat. A balanced diet is eating all the nutrients but in the right
amounts.
A balanced diet needs to include carbohydrate (for energy), Protein (for growth),
vitamins and minerals (to keep us healthy) along with fibre and water. (see Diet)
BIRD
One of the VERTEBRATES. A warm blooded animal that lays hard-shelled eggs
on land. Bodies covered in feathers eg thrush.
BLADDER
Organ in a human that stores urine. Urine leaves the bladder through a tube
called the URETHRA. In males the urethra leaves the body through the penis.
BACTERIA
Bacteria are microscopic organisms that can be found anywhere. Some bacteria
are helpful like those found in the soil that make things rot or the bacteria used to
turn milk into yogurt. Some are harmful and can make us ill, causing stomach
upset or a sore throat. (See micro-organism).
BALANCED DIET Our diet is what we eat. A balanced diet is eating all the nutrients but in the right
amounts. This would include lots of fruit and vegetables, pasta and cereals (for
vitamins, carbohydrates and fibre). Some fish, meat or cheese (for protein) and
only a small amount of fat, salt or sugar.
A balanced diet needs to include carbohydrate (for energy), Protein (for growth),
vitamins and minerals (to keep us healthy) along with fibre and water. (see Diet)
BLADDER
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Organ in a human that stores urine. (Urine is the yellow liquid you get rid of when
you go to the toilet) The kidney removes poisonous waste from the blood,
changes it into urine and stores it in the bladder
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BLOOD
A fluid in our body that consists of a clear watery liquid known as plasma and a
variety of other larger particles eg
red blood cells: these carry oxygen around the body and give the blood its red
colour.
white blood cells: these help fight disease
platelets:
very small cells that help the blood clot
Uses for blood: i) Transports food and oxygen to the cells.
ii) Transports waste away from the cells.
iii)Helps protect the body from infection.
iv) Helps regulate the body temperature (37C)
BLOOD VESSEL A tube that carries blood around the body. Large blood vessels are called arteries
or veins. Small ones are called capillaries. Arteries carry blood away from the
heart and veins carry blood back towards the heart.
BOIL
A liquid boils when it gets hot enough so that it evaporates inside (forming
bubbles) as well as at the surface.
BOILING POINT The boiling point of a liquid is the temperature at which it starts to boil
The boiling point of water is 100°C
BRAIN
Controls and coordinates all the major functions of the body. Where all the nerves
meet
BUNSEN BURNER
A piece of apparatus that burns gas and is used to heat apparatus. It has
an air hole that controls the flame temperature by regulating the flow of air into the
burner. When the air-hole is open: A hot, blue, roaring flame. When the air-hole is
closed: A cooler, smoky, luminous yellow flame. Not used to heat apparatus as it
is very sooty.
BURN
When something burns it reacts with oxygen giving off heat and light.
Burning is an example of a permanent change.
CARBON DIOXIDE
Is a colourless gas used by plants during photosynthesis and breathed out
by humans as a waste product. It is the gas that forms the bubbles in fizzy drinks
and is also sometimes put in fire extinguishers.
To test for carbon dioxide bubble it through lime-water which will turn cloudy.
Carbon dioxide is a compound of carbon and oxygen and has the formula CO2
CAPILLARIES
Tiny blood vessels that carry blood to the individual cells.
CAPILLARY ATTRACTION
A force which drags liquids up fine holes or cracks. It is what causes
porous objects soaking up water and allows blotting paper and towels to absorb
CARACTERISTIC Anything about of animal or plant inherits from its parents is a characteristic
eg. Characteristics of a shark: streamlined body, sharp teeth
Characteristics of a duck: webbed feet, waterproof feathers
CARBOHYDRATE
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Carbohydrates are starch or sugar like sweets, bread, pasta.
Carbohydrates provide us with energy.
Carbohydrates contain the elements carbon, hydrogen and oxygen.
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CARBON
Carbon is one of the chemical elements. All living things contain carbon.
Carbon is black. Coal and charcoal are made mostly of carbon. When you ‘burn’ a
piece of toast you are left behind with carbon. Diamond and graphite are both
made of pure carbon. When carbon burns it forms carbon dioxide gas.
CARBON DIOXIDE
Is a colourless gas used by plants during photosynthesis and breathed out
by humans as a waste product. It is the gas that forms the bubbles in fizzy drinks
and is also sometimes put in fire extinguishers. Carbon dioxide turns lime-water
cloudy.
Carbon dioxide is a compound of carbon and oxygen and has the formula CO2
CARNIVORE
An animal that eats only meat. (Carnivorous)
eg thrush, pike, ladybird
CELL
The basic unit of all life. All cells contain a NUCLEUS, CYTOPLASM , MITOCHONDRIA
AND A CELL MEMBRANE. Plant cells also have a CELL WALL, a LARGE VACUOLE and
sometimes CHLOROPLASTS.
CELL
A cell is another name for a battery. A battery would normally be several cells
joined together. The cell provides the chemical energy to push the electric current
around a circuit
CELL MEMBRANE
The living outer boundary of the cell. The membrane is selective in allowing what
passes through it (into or out of the cell).
Cells build up into tissues, tissues into organs and organs into organisms. Found
in ALL cells.
CELL WALL
The dead, outer edge to the cell. gives the cell strength. Made of cellulose. Found
ONLY in plant cells.
CHANGE STATE: The three states of matter are solid, liquid and gas.
A substance can be made to change state by heating it up or cooling it down
Changing from a solid to a liquid (by heating it) = melt
Changing from a liquid to a gas or vapour (by heating it) = evaporate
Changing from a gas to a liquid (by cooling it down) = condense
Changing from a liquid to a solid (by cooling it down) = solidify
All examples of changing state are reversible changes.
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CHEMICAL CHANGE
When a new substance is formed and a chemical reaction has taken place.
Examples of a chemical reaction are: DECOMPOSITION, COMBINATION,
COMBUSTION, RUSTING, PHOTOSYNTHESIS, OXIDATION and NEUTRALISATION
Signs that a chemical change is taking place are:
i. Heat given out ii. Colour change
A chemical change will usually be permanent.
eg Burning magnesium (to form magnesium oxide)
CHEMICAL REACTION
Any process where a new substance is formed (see Chemical Change)
CHLOROPLASTS
The part of a PLANT CELL that is green. Found only in certain plant cells
above ground. Chloroplasts contain chlorophyll which makes them look
green. They are where photosynthesis is carried out.
CHLOROPHYLL Chlorophyll is the substance that makes plants look green.
It is needed for photosynthesis to take place.
CHORDATES
Animals with a backbone. Have an internal skeleton. eg Lion, snake, frog.
COELENTERATES
Jelly-fish/sea anemones. Have central mouth surrounded by stinging tentacles eg
Portuguese Man of War
COLD-BLOODED
Animals whose body temperature alters with the temperature of the
surroundings eg fish. All animals except for birds and mammals are cold
blooded.
COMBUSTION
Another name for BURNING. A combustible material is one that burns easily.
Products of combustion: the chemicals produced when something is burnt. eg.
The products of combustion when wax is burnt are carbon dioxide and water.
COMMUNITY
A collection of all the animals and plants that live in a particular area.
COMPOUND
The substance formed when two or more elements are chemically combined
together.
eg HYDROGEN (element) + OXYGEN (element) = WATER (compound).
Other compounds: Copper sulphate, magnesium oxide, calcium carbonate
Note: the elements in a compound cannot be separated without a chemical
reaction taking place.
CONDENSE
Condensing is what happens when a gas turns to a liquid due to being cooled
down.
For example if steam touches a cold mirror it will condense and turn to drops of
water. (See Change of State). Condensing is a reversible change.
CONSUMER
Consumers are the animals in a food chain (Plants are called producers)
The first animal in a food chain is called a primary consumer
The second animal is called a secondary consumer.
Example food chain
Grass
(producer)
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rabbit
(Primary consumer)
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Fox
(secondary consumer)
COPPER
Copper is pink metal. It is a very good conductor of heat and electricity.
It is the metal that wires are made from. It is a metallic element.
CRUSTACEANS Animals that usually have 5 pairs of legs, eg crab, woodlouse. Belong to the
phylum of Arthropods.
CRYSTALLISATION
The process for obtaining the solute from a solution by warming the solution until
crystals start to appear and then letting the solution cool.
eg obtaining copper sulphate from copper sulphate solution.
CRYSTALS
A crystal is a solid in which the particles are arranged in a REGULAR pattern.
Crystals will often have flat sides and straight edges.
CURRENT
The rate at which electricity moves along a conductor. Measured in amperes
(amps) using an instrument called an ammeter.
CYTOPLASM
The living contents of a cell (excluding the nucleus). Found in ALL cells.
DAY
The time it takes a planet to revolve once on it axis. One Earth day = 24 hours
DECOMPOSE
When a compound is split apart into two (or more) simpler substances, usually by
heating.
eg if blue (hydrated) copper sulphate is heated it will decompose into anhydrous
copper sulphate (a white powder) and water.
DECOMPOSE
Another name for ‘rot’. A dead animal or plant will slowly decompose (rot away) if
left in the ground..
It is the bacteria and fungi in the soil that make an animal
decompose.
DECOMPOSER
An animal that lives on the rotting remains of other organisms. Decomposers help
in the recycling of dead material returning essential nutrients to the ground. eg
fungi, bacteria, various beetles, worms.
DENSITY
Mass per unit volume.
This means the mass (in grams) of one cubic centimetre of a substance.
The unit of density is GRAMS PER CUBIC CENTIMETRE (g/cm3).
Density is calculated as DENSITY = MASS / VOLUME
eg a block of iron with a volume of 3cm3 has a mass of 27g . This tells us the
density of iron = 27÷ 3, = 9g/cm3.
This means that the mass of one cubic centimetre of iron is 9 grams.
The density of water is 1 g/cm3. Anything with a density more than that of water
will sink and anything with a density less than water will float.
A substance with a LOW density will take up more space (volume) than a
substance with a high density.
DIAPHRAGM
A sheet of muscle across the body, above the abdomen but below the lungs, that
enables us to breath.
DIGESTION
Digestion is what happens to your food after you eat it. The food is broken down
by enzymes into simple chemicals that are then absorbed into the body. Digestion
takes place mostly in the intestine. (Although digestion actually starts in the
mouth)
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DIODE
An electrical component that only allows a current to flow in one direction.
DISEASE
A disease is an illness caused by a fungus, bacterium or virus.
Examples : Sore throat or upset tummy are often caused by bacteria.
Flu and measles are caused by a virus.
A lot of plant diseases are caused by fungi.
We can help stop the spread of disease by doing the following...
by washing our hands after going to the toilet or before preparing food.
by storing food at the right temperature (below 5°C) and cooking it properly.
by not sharing cups.
by using a handkerchief (or hand) over your mouth when you cough or
sneeze.
DISTILLATION
The name of the process used for obtaining the SOLVENT from a SOLUTION
eg obtaining pure water from sea water.
Fractional distillation is the process for separating two (or more) liquids from each
other. It relies on the liquids having different boiling points. eg i. obtaining alcohol
from beer ii. obtaining petrol from crude oil. The gases in air can be separated by
the fractional distillation of liquid air.
DISTILLATE
The liquid that has been distilled.
EAR
Used for HEARING. Rapid changes in air pressure cause the eardrum to vibrate.
The ear also controls BALANCE by making use of small tubes filled with liquid and
lined with tiny hairs.
ECLIPSE
Eclipse of the moon: when the Earth's shadow falls onto the moon, so that the
moon cannot be seen. Eclipse of the sun: When the Earth blocks out some of the
Sun's light so that it cannot all be seen.
ECOLOGY
The study of animals and plants in their natural environment.
ECOSYSTEM
A community of animals and plants and the habitat where they live.
EGG DUCT
See FALLOPIAN TUBE.
ELEMENT
The elements are the simplest of all chemicals. They are the building blocks from
which every other substance is made.
There are just over 100 elements.
Metals:
Non-metals:
Examples of some chemical elements with their symbol:
Copper Cu, calcium Ca, Iron Fe, Sodium Na, Magnesium Mg
Oxygen O, Nitrogen N, Carbon C, Helium He, Hydrogen H, Sulphur S, Chlorine Cl
Elements consist of only a single kind of atom and cannot be decomposed.
The elements are grouped together in the Periodic table
EMBRYO
The young child inside the uterus. While the child is only partly formed it is often
called a FETUS.
ENDOSKELETON An internal hard skeleton (as found in humans and other vertebrates).
See Exoskeleton
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ENERGY
Something has energy if it can be used to do any useful job of work. The unit of
energy is the joule. Different types of energy include:
Nuclear energy, electrical energy, heat energy, sound energy, light energy, kinetic
(speed) energy, potential (height) energy, chemical energy and strain energy.
Example of objects which contain energy:
Coal
has
chemical energy
A spinning flywheel
has
kinetic energy
A stretched elastic band has
strain energy
A brick on a shelf has
potential energy
Law of conservation of energy: Energy can never be created or destroyed, only
changed from one form to another
Examples of energy conversion: A falling ball converts potential energy to kinetic
energy.
A petrol engine converts chemical energy to kinetic, sound and heat energy.
Whenever anything slows down then kinetic energy is converted into heat energy.
RENEWABLE energy is energy that can be replaced and usually starts from the
SUN eg wind power, solar energy, hydroelectric energy, wave power. Renewable
energy is usually cleaner and causes less pollution. NON-RENEWABLE energy
cannot be replaced eg coal, oil and natural gas (these are also called FOSSIL
FUELS.
ENVIRONMENT
The conditions which effect the life and development of animals and plants within
the habitat. Examples of physical factors which effect the environment are air
temperature, soil pH, and air humidity.
ENZYME
An enzyme is a chemical that breaks down food in the gut into simple soluble
substances that can be absorbed into the blood stream in the small intestine.
An example of one enzyme is Amylase which turns starch into a simple sugar.
EVAPORATION
The process for obtaining the solute from a solution by warming the solution and
letting the solvent evaporate completely away. eg obtaining SALT from SALTY
WATER.
EXERCISE
Exercise is very important to help keep you healthy:
It strengthens muscles, helps keeps your heart healthy, improves your stamina
and makes you feel better.
Your heart beats faster when you exercise to get more food and oxygen to the
muscles.
EXOSKELETON An exoskeleton is the hard outside skin found on some animals.
Animals that have an exoskeleton include crab, lobster, and all insects.
EYE
Used for seeing. Contains a LENS which focuses light onto light sensitive cells
found in the RETINA.
FALLOPIAN TUBE
Sometimes called an EGG DUCT. Carries the eggs from the ovary to the
uterus. Where an egg is fertilized. The eggs take about seven days to
travel down the Fallopian tube.
FERMENTATION
The process where YEAST converts sugar into ALCOHOL and CARBON
DIOXIDE. It is a process used in the brewing industry (where the sugars in
wine or beer is changes to alcohol) and in baking where the carbon dioxide
makes the bread rise.
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FERTILIZATION
The fusion (joining) of the male and female gamete.
FILAMENT
i
II
Male part of a flower. Supports the ANTHER
The thin metal coil if wire in a light bulb that gets hot when a current flows
through it and glows. It is usually made of tungsten which has a very high
melting point.
FILTER
A piece of transparent, coloured plastic that absorbs some colours and not others.
FILTER
The process of separating a solid from a liquid by passing it through a piece of
filter paper.
Example. If you filter muddy water the clear liquid you collect is called the filtrate.
FILTRATE
The clear liquid that drips through the filter paper when filtering.
FILTRATION
The process used for separating a SOLID from a LIQUID eg obtaining SAND
from SALTY WATER.
FISH
One of the VERTEBRATES. A animal that lays soft jelly covered eggs in water.
Have scaly skin. eg trout.
FLATWORMS
Segmented worms, mostly parasitic eg tapeworm.
FLOWER
The part of a plant that contains the reproductive organs. Where the plant makes
seeds. Flowers that are insect pollinated (eg rose) have colourful or scented
petals to attract insects. Wind pollinated plants (eg grass) do not have petals but
still have flowers.
Male parts
Anther + filament = stamen
Pollen is made on the anther
Female parts
Stigma + style + ovary = carpel
Ovules (eggs) are made in the ovary
Sepals are tiny leaves that protect the bud
FLOWERING PLANTS
Plants that produce SEEDS. Eg grass, apple, oak, rose.
Non-flowering plants like ferns or moss make spores instead of seeds
(See Plant)
FOOD CHAIN
A list of organisms to show a simple feeding pattern within a habitat
eg CABBAGE LEAF  SLUG 
THRUSH 
FOX
A food chain always starts with a plant:
PLANT
 HERBIVORE

CARNIVORE
The arrows show the transfer of food energy from one organism to the next.
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FOOD WEB
A diagram that represents several interlinked food chains
FORCE
A Push or a pull. Measured in NEWTONS (n). A force can cause an object to SPEED
UP, SLOW DOWN OR CHANGE SHAPE. Examples of forces: friction, gravity, magnetism,
electrostatic charge. Forces usually work in pairs.
An object will speed up or slow down if the forces on it are not balanced.
If an object is stationary (or moving at a steady speed) then the forces on it must
cancel themselves out (we say that the forces are in equilibrium).
A force can cause an object to SPEED UP, SLOW DOWN OR CHANGE SHAPE
Four forces on an aeroplane.
Weight is caused by gravity.
Drag is caused by air resistance and is a kind of friction.
Lift is an upward force that keeps the plane in the air.
Thrust is a force that pushes the plane forward.
Examples of forces:
Friction (a force caused by things rubbing together. Friction makes things slow down)
Air resistance (when something moves through the air, air resistance slows it down. A
streamlined shape would reduce the air resistance so would go faster)
Gravity (pulls objects down towards the centre of the Earth. Gravity causes things to have
weight)
Magnetism (A magnet can attract iron or another magnet. Two similar poles will repel)
Upthrust (Upthrust is the force that makes things float or feel lighter in water)
An object will speed up or slow down if the forces on it are not balanced.
If the forces on an object are the same it will not move (or stay moving at a steady
speed)
FOSSIL FUEL
Fossil fuels are fuels made from the remains of dead animals or plants
The main fossil fuels are coal, oil and natural gas. Fossil fuels are fairly cheap and
easy to obtain but they are slowly running out (and cannot be replaced). They also
cause lots of pollution.
FREQUENCY
The rate at which something occurs.
In SOUND it means the number of sound vibrations that occur every second.
Measured in hertz (Hz). A higher frequency means a higher pitch
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FRICTION
A force which causes a moving object to slow down. Friction always acts in the
OPPOSITE direction to the direction of motion. Sometimes friction is an ADVANTAGE
eg slowing down a man with a parachute or the brakes of a car slowing it down; and
sometimes it is a disadvantage eg air resistance slowing down a car and using more
petrol, or bearings heating up.
Friction happens when two surfaces rub together
Rough surfaces have a lot of friction. Smooth surfaces have only a little friction.
Friction is a force which tries to slow things down.
Friction causes heat.
Without friction our shoes would have no grip on the floor and cars would not be able
to slow down or turn corners. (see Force)
Air resistance (or drag) is a kind of friction caused by air slowing down moving objects
(like a parachute or a car)
Friction can be reduced by using rollers or a lubricant like oil between the surfaces that
touch. (See Air Resistance)
Friction always tries to convert KINETIC ENERGY into HEAT ENERGY.
FRUIT
A fruit is the ovary of a plant and is where the seeds are formed.
It is a female part of the plant.
Examples of fruit: banana, apple, orange, tomato, cucumber
FULCRUM
The point on which a lever rests or is supported.
The further a force is from the fulcrum, the more effect it has on the load. see lever.
FUEL
A fuel is something we can burn to obtain heat energy (like coal, oil or wood)
FUNGI
A group of plants that do not possess green chlorophyll so cannot carry out
photosynthesis.
They take their food from the material they are growing on/in. They reproduce by
forming spores.
Examples of different fungi: mushroom, yeast, mould.
Fungi (along with bacteria) are very important in the food chain for the recycling of
nutrients in the soil.
Some fungi are harmful and can cause disease in crops (eg potato blight).
Some fungi are useful to man eg yeast which is used to ferment sugar and produce
alcohol in the brewing industry.
FUSE
A fuse is a short length of wire designed to melt (or ‘blow’) when the current flowing
though it gets too high. It is a used as a safety device to cut off the supply of electricity
when something goes wrong. All 13A plugs contain a fuse. (See Appendix 3 for the symbol).
GALAXY
A large number of stars grouped together. Our sun is in a galaxy called the Milky Way.
The universe contains many galaxies.
GAMETE
Sex cell. One of the cells that fuse during sexual reproduction.
It is from the gametes that the young animal or plant inherits characteristics from its
parents.
MALE GAMETE:
in plants = pollen,
in animals = sperm
FEMALE GAMETE:
in plants = ovule,
in animals = ovum.
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GAS
One of the three states of matter. (the other two are solids and liquids).
A gas always completely fills its container and has no fixed shape
A gas can be compressed (squashed into a smaller space).
If a gas is cooled down it will condense and form a liquid.
The particles in a gas are far apart and move rapidly in all directions
GERMINATION
Germination is when seeds start to grow.
Seeds need three conditions to germinate:
1. Warmth, 2. Air (Oxygen) and 3. Water
GERMINATION PERIOD The time between planting a seed and the first growth of the new plant
GESTATION PERIOD
The time taken for a baby to grow inside its mother.
The gestation period for a human is 9 months (about 38 weeks)
GILLS
Gills are used by a fish to take oxygen from the water.
GRAPHITE
A form of carbon. Graphite is the black substance inside pencils (the pencil lead).
Lead used to be used in pencils but is not used any more due to it being poisonous.
GREENHOUSE EFFECT Certain gases in the air like carbon dioxide and methane trap heat from the sun
and cause the air to heat up (in the same way as the inside of a car or greenhouse
heat up on a sunny day). The greenhouse effect is responsible for global warming.
GRAVITY
Gravity is the force that pulls all objects down towards the centre of the Earth.
Gravity causes objects to have weight.
All the objects in the solar system have gravity. The bigger the planet, the more gravity
it has and so the more things will weigh.
GUT
See ALIMENTARY CANAL
HABITAT
The place where an animal or plant makes its home
eg woodland, fresh-water stream, puddle.
HEART
The heart is an organ to pump blood to and from the lungs and around the body. The
heart is made mostly of muscle and contains valves to control the direction of blood
flow.
To keep the heart healthy we should eat a diet low in fat and salt, eat lots of fruit and
vegetables and take regular exercise. Smoking and drinking alcohol can also damage
the heart. (See Keeping Healthy)
HEART RATE
The speed at which our heart pumps. The normal heart rate of a child is 80 b.p.m
(beats per minute) and an adults average heart rate is 72 b.p.m..
Our heart rate will go up when we take exercise because our muscles need more food
and oxygen so the heart has to pump faster. (see Pulse)
HERBIVORE
(Herbivorous) An animal that eats only plants. (leaves, seeds, berries, bark etc) eg
snail, mouse
HORMONE
Chemicals in the body that control certain functions such as the rate of a boy/girls
growth. Hormones are made in several parts of the body. The hormones responsible
for the changes at puberty are made in the testes or ovaries.
HOST
The organism on which a parasite is living
eg if a flea lives on a fox then the fox is the host and the flea the parasite.
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HYDROCARBON A compound containing only the elements HYDROGEN and CARBON. eg petrol, wax
Hydrocarbons will burn to form the compounds carbon dioxide and water.
IMMISCIBLE
Two liquids are immiscible if they will not mix together (like oil and water)
IMPERMEABLE
Impermeable means waterproof. An impermeable rock (like granite) will not let water
seep through it. (The opposite of impermeable is permeable)
INSECTS
Animals that have 3 pairs of legs, 3 parts to the body and usually 2 pairs of wings eg
butterfly, ant. The eggs from an insect hatch into larvae. The larva is the young form
of an insect. A caterpillar is the larva of a butterfly. A maggot is the larva of a fly.
Useful insects include the bee which helps pollinate flowers and also provides us with
honey. A lot of insects are decomposers (eg fly and many beetles) and play an
important part in the ecosystem recycling dead plants and animals.
Insects can carry disease (eg mosquito carries malaria). Insects can harm food crops
which either get eaten or damaged by insects.
INSOLUBLE
Cannot be dissolved. eg sand is insoluble in water; sugar is insoluble in petrol NOTE:
when using the words soluble or insoluble then you should give the name of the
solvent being used.
INSULATOR
Electrical insulator: A material that does not allow electricity to flow through it (like
plastic or glass).
Thermal insulator: A material does not allow heat to pass through it easily (like wool or
plastic)
A good insulator will be a poor conductor
A base of saucepan is made of metal because metals are good conductors of heat,
The handle is often made of wood because wood is a good insulator
IRREVERSIBLE CHANGE
A change in a substance that is permanent.
Examples of irreversible changes are BURNING toast, COOKING a cake or an
egg, RUSTING. (See Chemical Change)
INVERTEBRATES
Animals without a backbone. All animals except for mammals, birds, reptiles,
amphibians and fish are invertebrates.
KEEPING HEALTHY
i.
ii.
iii.
iii.
iii.
iv
KIDNEY
Take regular exercise. This improves stamina and keeps the heart healthy
Eat a diet low in fat and salt (fat can damage the heart). (see Balanced Diet)
Eat lots of fruit and vegetables (which contain important vitamins and minerals)
Avoid a lot of alcohol (alcohol can damage the heart and liver)
Do not smoke (smoking can damage the lungs)
Do not take drugs (drugs can damage the liver)
i) Removes waste (urea) from the blood. ii) Removes water from the blood and so
controls the blood concentration. The liquid which the kidneys remove is called URINE
which passes down the URETER to the bladder.
LARGE INTESTINE
The last stage in the GUT. An organ in our body where water absorption takes place.
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LDR
Light Dependant Resistor. This is a resistor which has has a high resistance in the
dark and a low resistance in the light.
LEAVES
Where photosynthesis is carried out in a plant. Have a large surface area to absorb the
sunlight.
LED
Light Emitting Diode. A small device that gives out light but only uses a tiny current. It
allows a current to only flow in one direction.
LEVER
A device for increasing the effect of a force. The load needs to placed near to the
fulcrum and the effort (or applied force) further from the fulcrum.
LEVER LAW
Sometimes called the law of MOMENTS. When a lever is balanced then this law
applies:
Force on the left x its distance from the fulcrum = force on right x its distance from the fulcrum
6cm
9cm
4N
ie on left....
Fulcrum
6N
4n x 9cm = 36
on the right... 6n x 6cm = 36
LIEBIG CONDENSER
A special glass tube used to cool down and condense a hot gas. Water flows through
an outer glass jacket and this keeps the inner glass tube cool.
LIFE CYCLE
The main stages in the life of an animal or plant.
The human life cycle is:
unborn baby  Baby  Child  (Puberty) Adolescence  Adult  Old age
The life cycle of a flowering plant is:
Pollination  Fertilization  Seed dispersal  Germination  Growth of plant
LIFE PROCESSES
There are seven processes that are carried out by all living organisms
Movement, Growth, Reproduction, Nutrition (feeding), Respiration, Excretion (getting
rid of waste) and Respond to a stimulus
(see Living Things)
LIGAMENT
Ligaments hold the bones together at each joint in your body.
LIGHT RAY
A light ray is shows the path of light in a diagram. A light ray should be drawn as a
single straight line with one arrow on it.
LIQUID
In liquids the particles are still close together but only held together by WEAK electrical
forces which leaves them free to slide over one another. A liquid has a fixed volume
but takes up the shape of its container.
LIME
Sometimes called quicklime. Made of a compound called calcium oxide. (See calcium
oxide). It is alkaline oxide and is used in agriculture to neutralise an acid soil.
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LIVER
The largest organ in the body. It helps keep a balance of nutrients in the body and can
also help remove poisons from the body. This is why the liver is often damaged when
a person drinks too much alcohol (a poison) or takes drugs.
LUMINOUS
A luminous object is one that gives out light eg the sun, the stars, a light bulb or
candle.
(Remember, the Moon is NOT luminous and gives out no light of its own. We see the
Moon due to light from the Sun being reflected from the Moon back to the Earth)
LUNGS
Organ in the body that is responsible for gaseous exchange
i) Transfers oxygen to the blood.
ii) Removes carbon dioxide from the blood.
MALLEABLE
Malleable means can be hammered into thin sheets. Most metals like gold, copper or
lead are malleable.
MAGNET
A magnet is a material that produces a magnetic force.
All magnets have two poles..
The pole is the part of a magnet where the magnetism is strongest.
The only common material that magnets attract (stick to) is iron.
All magnets have two poles (North seeking pole and South seeking pole)
Similar (like) poles repel (push apart) and different (unlike) poles attract each other.
Magnets are used to make electric motors and also to separate iron from other
materials.
MAGNETIC FIELD
.
ie
Invisible lines of force that extend into
space around a magnet. The arrows on
the magnetic field lines point from north to
south. Magnet field lines can be shown
using iron filings or by using a plotting
compass
MAMMALS
One of the VERTEBRATES. The young are
born alive. The females have mammary glands and suckle their young from nipples on
mammary glands. Have hair or fur on their bodies eg mouse, man. Warm blooded.
MASS
The mass of an object is a property of the object which NEVER changes. It is a
measure of an objects resistance to a change in motion. Mass is measured in
kilograms (or grams)
MENISCUS
The curved surface found on the surface of a liquid. NOTE: Any readings taken of the
volume of water in a container should be taken to the LOWER side of the meniscus.
METAL
An element that has most of the following properties: Malleable, ductile, shiny, good
conductor of heat and electricity. Metal oxides, if they dissolve, form ALKALINE
solutions. Eg copper, iron, tin, gold.
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MICRO-ORGANISM
A micro-organism is a living thing that is so small you need a microscope to
see it. Micro-organisms are either fungi, bacteria or viruses .
Helpful micro-organisms: yeast is a fungus that is used for making bread or beer
Bacteria that live in the soil are helpful as they cause things to rot and provide food for
plants
Bacteria are also used to term milk into yogurt or cheese.
Harmful micro-organisms:
Bacteria, viruses and fungi can all cause disease
Bacteria can cause a tummy upset or sore throat, viruses cause flu or measles
Bacteria can also cause food poisoning. (See Disease)
MINERAL
A naturally occurring substance from the ground, usually crystalline. eg Malachite
MITOCHONDRION Mitachondria are where respiration is carried out in all cells. They provide the cell
with energy. (see cell)
MIXTURE
At least two substances present that can be separated without a chemical reaction
taking place. No new substance is formed when a mixture is separated.
Examples of mixtures: AIR, SEA WATER, INK.
The substances in a mixture can be present in any proportion.
(see separating mixtures)
MOLECULE
The particle formed when two or more atoms chemically join together.
MOLLUSCS
Animals that have muscular foot and soft body eg slug, snail, oyster.
MOON
The Moon is a natural satellite of the Earth. (A satellite is an object that revolves
around a planet). The Moon orbits the Earth once every 28 days. The moon does not
give out light of its own. We see the moon due to light from the Sun being reflected
back to the Earth. (See Phases of the Moon)
A small plant. It has no proper roots. It reproduces spores. Live in damp, shady places.
MOSS
MUSCLE
Muscles hold the bones in place and help us move. Muscles usually work in pairs.
When one muscle contracts (or gets shorter and pulls) the other muscle relaxes.
NECTARY
Part of a flower that contains nectar to attract insects. Helps with POLLINATION
NEUTRAL
a liquid with a pH value equal to pH 7. Example: water, ethanol
NEWTON
A Newton (N) is a unit of force. On Earth a mass of 100g weighs about 1 Newton.
NON-FLOWERING PLANTS
Plants that do NOT produce seeds. Eg algae, moss and fungi.
NON-METAL
An element that has most of the following properties:
Brittle, poor conductor of heat and electricity. Non-metal oxides, if they dissolve, form
ACIDIC solutions. Note: CARBON, even though it conducts electricity, forms an
ACIDIC oxide and is therefore classed as a non-metal.
NUCLEUS
Controls the function and behaviour of the cell. Found in ALL living cells. Contains the
GENETIC MATERIAL.
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NUTRIENT
A substance found in food that is needed to help us grow and stay healthy.
Types of nutrient:
Carbohydrates (starch and sugar, found in bread, pasta and sweets) give us energy
Proteins (found in meat, fish and cheese) are needed for growth and repair of cells.
Vitamins and minerals (found in fresh fruit and vegetables) keep us healthy.
(See Balanced Diet)
OMNIVORE
An animal that eats plants and meat. (Omnivorous)
eg rat, human
OPAQUE
A material is opaque if it does not allow light to pass through it.
Brick and wood are opaque. (see Transparent and Translucent).
Opaque objects form the best shadow by blocking light.
ORE
A mineral from the ground from which a metal can be obtained.
ORGAN
An organ is a part of our body with a particular job to do. Examples:
Heart: pumps blood
Lungs: add oxygen to the blood and removes carbon dioxide
Ears: hearing and balance Brain: Co-ordinates and controls our body
Skin: keeps out germs
Kidney: removes poisonous waste from the blood
Eyes: Seeing
Stomach and Intestine: digests food
ORGANISM
The name we give to any animal or plant.
Examples of different organisms: dog, amoeba, flea, bacteria, daisy.
OVARY
The part of a flower where the seeds are formed,. Contains the OVULES. After
fertilization the ovary will often form a FRUIT.
OVARY
Where eggs/ova (female gamete) are manufactured.
OVULES
The part of a flower that contains the FEMALE GAMETE. The ovules will swell and
become seeds after fertilization.
OVUM
Another name for the egg cell found in an animal. The ovum contains the female
gamete (see Gamete). It is from genes in the ovum (egg) that we inherit
characteristics from our mother.
PARALLEL CIRCUIT
In a parallel circuit the current divides and follows more than one path.
This diagram shows a circuit diagram of two bulbs joined in parallel with a cell.
This would be the usual way to join several components to one battery
Normal house lights are wired in parallel.
(See Series Circuit)
PARASITE
An animal or plant that lives on (or inside) the body of another living organism eg
leech, flea, tapeworm
PENIS
An organ found on male mammals. Contains a tube called the urethra. Where urine
and sperm leave the body.
PERMEABLE
A rock that allows water to soak into it is called permeable. Chalk and limestone are
permeable rocks. A permeable rock is porous (full of tiny holes).
The opposite of permeable is impermeable. Granite is an impermeable rock.
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PETALS
Part of a flower that attracts the insects using scent and colour. This is to help
POLLINATION take place.
pH SCALE
A scale of numbers (from 1 to 14)which shows how acidic or alkaline a liquid is. pH 7
is neutral. Less than pH 7 is acid. More than pH 7 is alkali. The nearer to pH 7 a
solution is the weaker it becomes (ie pH6.5 is a very weak acid)
PHOTOSYNTHESIS
The process by which plants manufacture sugar using carbon dioxide from the air and
water from the soil.
Energy for the process comes from sunlight, absorbed with the help of chlorophyll.
Oxygen is released as a waste product. Takes place in the chloroplasts.
NOTE: photosynthesis takes place only during the day (or when there is light).
Word equation:
CARBON DIOXIDE + WATER ----> SUGAR + OXYGEN
(reactants)
(products)
PHYLUM
One of the divisions used in the classification of animals. EG Phylum Chordata are the
VERTEBRATES
PITCH
How high or low a sound is. The pitch of a vibrating object can be increased by:
i) making it shorted
ii) Making it weigh less.
In the case of a vibrating string making it tighter.
PLACENTA
An organ that supplies the developing embryo with food and oxygen from the mother's
blood. Waste (carbon dioxide and urea) travels back through the placenta from the
embryo to the mother. Other substances (alcohol, nicotine, drugs) can also travel
through the placenta and these can effect the development of the embryo. Blood cells
do NOT pass through the placenta.
PLANET
A non-luminous body in orbit around the Sun. It is held in orbit around the sun by the
pull of the sun's gravity.
PLANT
A flowering plant has four main parts:
1. Leaves (where photosynthesis takes place): (Nutrition)
2. Stem (to transport food and water around the plant
3. Roots (to support the plant)
4. Flower (where seeds are made) (Reproduction)
(See flower)
POLLINATION
When pollen reaches the stigma during reproduction in a flowering plant. There are
two main methods of pollination: Insect pollination (eg as in rose, apple); wind
pollination (eg as in grass).
Cross-pollination is when one plant pollinates another (as in the examples above)
Self-pollination is when a plant pollinates itself.
POOTER
Used in ecology to sample small invertebrate. It consists of a small glass bottle
containing two tubes. You suck on one tube and the animal gates drawn down the
other into the bottle.
POPULATION
A group of animals or plants of the same species living in a particular area.
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POWER
The rate at which energy is converted from one form to another. The rate at which
work is done.
[ie the number of joules per second
In electricity the rate at which electricity is used. Power = volts x amps
Units of power = WATTS]
PRECIPITATE
The insoluble solid formed when either two liquids react together or a gas reacts with a
liquid. eg Carbon dioxide reacts with limewater to form a white precipitate of calcium
carbonate.
PREDATOR
An animal that hunts for food. eg hawk, pike.
The food it hunts for is known as its prey. (See Prey)
PREY
An animal that is eaten by another animal is known as its prey.
Look at the following food chain: Lettuce  Slug Thrush  Fox
The slug is the prey of the thrush.
The thrush is a predator (of the slug) and the prey of the fox.
The fox is the predator of the thrush
PRESSURE
Force per unit area. This means the force (in Newtons) on one square metre (or
square centimetre) of area. Pressure is calculated as PRESSURE = FORCE / AREA
The unit of pressure is NEWTONS PER SQUARE CENTIMETRE (N/cm2).
If a force presses against a small area then the pressure will be high.
If the same force pushes on a large area the pressure will be less.
eg Why does it help to wear large boots walking in snow?
Answer: because with large boot your weight is spread out more making the pressure
on the snow LESS.
eg
Why are football studs used? answer because football studs have a small area.
This increases the pressure on the ground so they sink in and help stop the
player slipping.
PRODUCER
The first organism in a food chain. Always a green plant. Green plants are the only
organisms that can carry out photosynthesis and produce their own food from simple
chemicals in the soil and air. Note: fungi do not possess chlorophyll and so are NOT
considered as producers
PROTEIN
Proteins are an important part of our diet as they are needed for normal growth.
Foods rich in protein include meat, fish cheese and milk.
PROSTATE GLAND
Gland in the male that produces a liquid to help nourish the sperm.
PROTOZOA
Single celled animals eg amoeba
PUBERTY
The time in a child’s life when his/her sex organs start to develop. The changes are
brought on by HORMONES in the body. Puberty normally happens when a boy is
between 11 years old and 14 years old and slightly earlier in girls.
After puberty a boy can produce sperm and a girl will produce eggs.
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PULSE
The pulse is how we can measure our heart rate. Each pulse is one beat of the heart.
At certain points in our body we can feel the increase in blood pressure every time our
heart beats.
We can normally feel the pulse at our wrist and at the side of the neck.
The normal pulse for a child is 80 beats per minute. Our pulse will increase when we
take exercise (See Heart Rate).
PURE
Only a single substance present. Not able to be separated into any other substance
without a chemical reaction taking place.
QUADRAT
A square frame of wood (or area of land), often 1mx1m, used during ecology to
estimate populations.
REACTION
A chemical reaction ( or chemical change) takes place whenever a new substance is
formed. The signs of a chemical change are:
i) a change in temperature (eg getting warm) ii) a change in colour.
(See chemical reaction)
REDUCE
(Reduction) To remove the oxygen from a compound eg Zinc will REDUCE copper
oxide to form copper and zinc oxide. Reduction is an important way of obtaining metals
from their ores eg In the steel industry the carbon in COKE is used to take the oxygen
away from the iron ore (containing iron oxide) to leave molten iron.
REDUCING AGENT
An element good at removing oxygen from a compound (see Reducing)
eg carbon is used as a reducing agent when it removes oxygen from iron oxide.
RELAY
A relay is a kind of switch that contains an electromagnet made from a coil of wire. It
has four connections, two for the coil and two for the switch. The coil can be operated
by a very small current, but the relay contacts can switch a much larger current.
REFLECTION
When light bounces off a smooth surface (eg a mirror) and forms an image behind it.
REFRACTION
When light gets bent by passing from air into water or glass (or passing back again).
REPTILES
One of the VERTEBRATES. An animal that lays soft shelled eggs on land. Bodies
covered in hard scales. eg snake, lizard
RESIDUE
The solid remaining in the filter paper after filtering
(or any other small amounts of solid left after an experiment).
RESISTANCE
The property of a conductor that reduces the current flowing through it.
[Resistance is measured in OHMS, and can be calculated using the formula V=IR
where V=voltage, I=current and R=resistance]
RESISTOR
An electrical component that reduces the amount of current flowing in a circuit.
RESPIRATION
A process by which all living organisms release energy from sugar. Oxygen is needed
for the process.
Carbon dioxide and water are released as waste products.
Word equation: SUGAR + OXYGEN ----> CARBON DIOXIDE + WATER
NOTE: Even though respiration takes place all the time (in animals and plants) but
during the day in plants photosynthesis is a more rapid process.
Respiration provides energy for vital processes such as growth, cell repair,
reproduction, chemical reactions in the cell, movement and warmth.
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ROOT
Part of a plant that absorbs water and dissolved mineral salts from the ground.
The root also supports the plant in the soil.
A root will often have root hairs to increase its surface area.
ROUNDWORMS Tiny non-segmented worms. Mostly parasitic eg ring-worm.
SAPROPHYTE
A decay organism. Saprophytes cause the remains of organisms to rot. They are vital
for the recycling of nutrients into the ground. eg fungi and bacteria.
SATELLITE
An object in orbit around a planet. eg the moon is a natural satellite of the Earth. There
are also many artificial satellites around the Earth eg Meteostat is a weather satellite.
SATURATED SOLUTION
A solution that cannot dissolve any more solid unless the temperature is changed.
NOTE: if the temperature increases the solution will not be saturated any more as it
will be able to dissolve more solid.
SOLUBLE
Can be dissolved. eg Salt is soluble in water; iodine is soluble in alcohol
SCAVENGER
An animal that lives from the remains of other animals.
SEPALS
Part of a flower. Small green leaves to protect the bud.
SERIES CIRCUIT
eg shrimp, vulture.
In a series circuit the current follows a single path and does not divide.
The current will be the same in every part of a series circuit
This picture shows a circuit diagram of two bulbs joined in series with a cell.
Two bulbs joined in series will be dimmer than one bulb.
If one bulb breaks the other will go out.
(See Parallel Circuit)
SEPARATING MIXTURES
A suspension of an insoluble solid (like chalk) can be separated from water by filtering.
Something dissolved in water (like salt) can be separated from water by evaporating
away the water.
Evaporation separates the solute from a solution
Distillation separates the solvent from a solution
A separating funnel separates two immiscible liquids
Iron can be separated from other materials by using a magnet
Separating mixtures involves no chemical change ie no new substance is made.
(See mixtures)
SEXUAL REPRODUCTION
Reproduction that requires fertilization. eg production of seeds in plants (grass,
daffodil). Most animals (including humans) reproduce by sexually.
All multi-cellular animals can reproduce sexually.
Disadvantage: often a slow process
Advantage: offspring are different to parents. This allows natural selection and
accounts for the evolution of different species.
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SHORT CIRCUIT When a piece of wire allows electricity to take a ‘short cut’. A short circuit of a battery
(when a wire connects the positive to the negative terminal on a battery ) can be very
dangerous. The wire may get hot and the battery and will always run down very
quickly. A bulb that has been short circuited will not light up
In this circuit bulb B will be not light up because
the current flows along the wire around the bulb.
This happens because the wire has a much
lower resistance than the bulb.
SKELETON
Made up of rigid BONES. Provides a framework to support the other organs. Muscles
and tendons are attached to the bones to hold the skeleton in shape.
SKIN
Protects the body from germs. Blood capillaries in the skin open and close to help
regulate our body temperature. Stops us drying out
SMALL INTESTINE
Organ where most of the digestion/absorption of food takes place. The small intestine
is lined with tiny villi which increase its surface area.
SOLID
In a solid the particles are held rigidly together by STRONG electrical forces and can
only just vibrate. A solid has a fixed volume and fixed shape.
SOLUTE
The SOLID that has been dissolved to make a solution. eg When salt is dissolved in
water then the salt is the solute.
The solute is separated from a solution by EVAPORATION.
SOLUTION
The liquid obtained by dissolving one substance in another.
SOLUTE + SOLVENT = SOLUTION eg SALT + WATER = SALT SOLUTION
SOLVENT
The LIQUID used to make a solution.
eg When salt is dissolved in water then the water is the solvent.
Examples of good solvents include WATER, PETROL, ALCOHOL
The solvent is removed from a solution by DISTILLATION.
SOUND
To produce a sound something must be vibrating.
We hear the sound when vibrations in the air reaching our ears.
Sound travels quicker in solids and liquids than it does in air.
Sound cannot travel through a vacuum.
The pitch of a sound is how high or low it is. (See Pitch)
If the frequency of the vibrations increases the pitch will be higher
(frequency = the number of vibrations per second)
The volume of a sound is how loud it is. (See Volume)
The amplitude of a wave is its size: larger amplitude = louder volume
SPEED
How far something moves in one second (or 1 hour).
Normal metric unit = Metres per second (m/s). Speed = distance ÷ time
Example a ball takes 2 seconds to roll 5 metres. What is the average speed of the ball
Speed = 5 ÷ 2
 speed = 2.5 m/s (this is the average speed because the ball may not have been
going the same speed for the whole distance).

SPERM
Science Dictionary April 2014
The sperm carries the male gamete in an animal. It has a tail and can swim around.
The sperm is much smaller than the egg (ovum). (see Gamete).
It is from genes in the sperm that we inherit characteristics from our father.
Page 24.
SPERM DUCT
A tube that carries sperm from the testis to the urethra.
STAMEN
The male part of a flower. Where the pollen is made. Is made up from a FILAMENT
and ANTHER.
STAR
A large mass of hot gas that gives out vast quantities of heat, light and other radiation.
Our Sun is a typical (although quit small) star.
STATES OF MATTER
The three states of matter are SOLID, LIQUID and GAS.
(See Physical Change and Solid, Liquid or Gas)
STEM
Transports food and water around a plant. Holds apart the leaves and flowers.
STIGMA
Part of a flower where pollen lands during pollination.
STOMACH
Part of the alimentary canal where food is held before it is passed into the small
intestine. Some digestion takes place in the stomach.
STYLE
The part of a FLOWER that connects the stigma to the ovary
SURFACE TENSION
The force on the surface of a liquid that causes the liquid to behave as if it were
covered by a thin skin. Surface tension can support light objects such as an insect on
the surface of water.
It is destroyed by liquids such as soap and detergent.
SUSPENSION
A mixture containing tiny particles of solid mixed with water.
Eg a suspension of chalk in water.
The solid in a suspension can be separated by FILTRATION.
SWITCHES
A switch is used to start or stop electricity flowing in a circuit.
When a switch is OPEN the electricity cannot flow (a bulb would be OFF)
When the switch is CLOSED the electricity can flow (and a bulb would be ON)
SPST (Single Pole Single Throw): This is an ordinary on/off switch.
SPDT (Single Pole Double Throw): Works like railway-line points. Can connect
electricity to one wire or another.
Push switch, similar to a normal bell switch, only on while it is pressed.
Reed switch, operated by a magnet.
(see Relay)
SYNTHETIC
Synthetic means ‘man-made’. A synthetic substance is not natural. Examples of
synthetic (man-made) materials are plastic, brick and glass
TEMPORARY CHANGE A change that is not permanent like evaporation, melting, solidifying,
condensation or dissolving. (See Changing State and Physical Change)
TEMPERATURE A measure of how hot or cold something is.
Temperature is normally measured using a thermometer in degrees Celcius (°C)
Some useful temperatures to know:
Boiling point of water
= 100°C
Melting point of water
= 0°C (This is the temperature of melting ice)
Human body temperature = 37°C
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THERMOMETER An instrument used to measure temperature.
THORAX
The part of an animal between the head and the abdomen. In a human the thorax
contains the heart and lungs. In an insect the thorax is where the wings and legs are
attached.
TESTIS
Where sperms (male gamete) are manufactured in a human.
TOP CARNIVORE The carnivore at the end of a food chain. eg fox, pike.
TRACHEA
Another name for the windpipe
TRANSMISSION When light passes straight through something like a piece of transparent paper.
TRANSLUCENT Something is translucent if some light can pass through it but no detail can be seen
(like a sheet of paper). A translucent object will still make a shadow because it blocks some of the light.
TRANSPARENT Something is transparent if light can shine through it (like a sheet of glass)
A transparent object will usually not form a shadow.
TRANSPIRATION Transpiration is the name of what is happening when a plant loses water. Water enters
the plant through the roots, travels up the stem and leaves the plant through its leaves
TULLGREN FUNNEL
Used in ecology to sample small invertebrates in litter. How it works: Some litter is
placed in a funnel with a lamp over the top. The animals move away from the light and
heat and eventually fall through the base of the funnel.
UMBILICAL CORD
A tube that connects the baby to the mother (before it is born). It consists of an
artery and vein that connects the embryo's blood circulatory system to the
placenta.
UNIVERSE
The name given to the collection of everything that exists in space.
URETER
The tube that carries urine from the kidney to the bladder
URETHRA
The tube that carries urine from the bladder to outside the body.
UTERUS
Organ where the embryo/foetus develops.
VACUOLE
A large vacuole is found only in plant cells. It contains cell sap and helps keep the cell
rigid.
VACUUM
A vacuum is a space that contains nothing at all (not even air)
Sound cannot travel through a vacuum.
VARIATION
Variation is the word which describes differences between one animal (or plant) and
another of the same species. These characteristics might be inherited from the
parents (or genetic) or they may be environmental.
Eg The colour of your eyes was information inherited from your parents (genetic)
The height of a plant could be due to the available light (environmental)
VEINS
Blood vessels that carry blood towards the heart. (see ARTERIES)
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VERTEBRATES
Animals with an internal hard skeleton. The vertebrates include mammals, birds,
reptiles, amphibians and fish.
VIRUS
A virus is a tiny micro-organism that lives inside the cell of another animal or plant. A lot of
viruses can cause diseases like flu or measles (See Micro-organism)
VITAMIN
vitamins are substances in food that we need a small amount of to keep us in good health.
Examples:
Vitamin C is found in lemons and oranges and green vegetables.
Lack of vitamin can cause unhealthy gums and an illness called scurvy
(See Nutrient)
VOLTAGE
The push, or potential difference, that tries to push an electric current around a circuit.
Measured in volts using an instrument called an ammeter.
VOLTMETER
An instrument used to measure potential difference (voltage). It is placed in parallel
with the conductor being tested and has a high resistance.
VOLUME
How loud or soft a sound is. The AMPLITUDE of a sound wave controls the volume.
WARM-BLOODED
Animals whose body temperature is constant are called warm-blooded. eg
Human: body temperature 37oC.
The only warm-blooded animals are birds and mammals.
WATER
Water is a colourless liquid. It is needed by all animals and plants.
Water is a compound of hydrogen and oxygen and has the formula H2O
Water boils at 100°C (called its boiling point)
Water freezes at 0°C (called its melting point)
Water is the most common liquid on Earth.
WATER CYCLE
Condensation
Evaporation
Heat from the Sun (1) causes water in the sea to evaporate and form water vapour (2). As the water
vapour rises it cools down and condenses to forms clouds (3). Wind blows the clouds over land where the
water falls as rain (4). The rainwater collects into rivers (5) and flows back to the sea to be reheated by
the Sun and the cycle starts again.
Note:
Evaporation = Liquid to gas
Condensation = gas to liquid
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WEIGHT
The weight of an object is caused by the pull of gravity and will change if gravity
changes. ie If gravity gets less then the weight will also get less. Weight is measured in
newtons.
The pull of the Earth's gravity is approx. 10N on every 1kg (ie 1N on 100g)
eg the mass of a block of butter = 500g On the Earth it's weight will be 5 newtons. On
the Moon its mass will be the SAME as on the Earth but it's weight will be LESS.
YEAR
The time it takes a planet to complete one full orbit around the sun. On Earth one year
= 365.24 days.
YEAST
A single celled FUNGUS used in baking to make bread rise and in brewing to make
alcohol. (see fermentation)
ZYGOTE
The cell formed by the fertilization of a male and female gamete.
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APPENDIX 1
Elements with their symbol
 Hydrogen H
 Carbon C
 Oxygen O
 Nitrogen N,
 Sulphur S,
 Magnesium Mg,
 Sodium Na,
 Chlorine Cl,
 Calcium Ca,
 Copper Cu,
 Iron Fe,
 Helium He
Simple formulae:








Water H2O
Carbon dioxide CO2
Oxygen O2,
Methane CH4,
Sodium chloride (salt) NaCl,
Hydrochloric acid HCl,
Sodium hydroxide NaOH,
Calcium carbonate CaCO3
(chalk, limestone)
Some materials you need to be able to recognise
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APPENDIX 2
Measurement
Quantity
Unit
Method of measurement
Distance
Metre (m)
Use a metre rule
Time
Second (s)
Stop watch, timer
Mass
Kilogram (kg)
Use a top pan balance
Force
Newton (N)
Spring balance (newton metre)
Weight
Newton (N)
Spring balance or scales
Energy
Joule (J)
Energy meter
Pressure
Newton per square
centimetre (N/cm2)
Density
Grams per cubic centimetre
(g/cm3)
Volume
Cubic centimetre (cm3)
Area
Square centimetre (cm2)
Current
amp, (A)
Use the formula:
Pressure = force
area
Use the formula :
Density = mass
volume
For a rectangular block use the formula
Volume = height x width x length
For a liquid, use a measuring cylinder.
use the formula:
area = length x width
Use an ammeter
Voltage
Volt (V)
Use a voltmeter
Temperature
Degrees Celsius ( C)
Use a thermometer
Speed
Metres per second (m/s)
Use the formula:
Speed = distance
time
NOTE: Items written in italics do not need to be learnt for your CE exam. They are put in for your own
interest.
SOME USEFUL FIGURES
Mass of a 13 year old pupil
Weight of a 13 year old pupil
Height of a 13 year old pupil
Normal body temperature of a human
Boiling point of water
Freezing point of water
Density of water
Mass of a new-born baby
Thickness of a sheet of paper
About 40 kilograms (40kg)*
About 400 newtons (see WEIGHT)*
About 1.5 metres (1.5m, = 150cm, =1500mm)*
37 degrees Celsius (37 oC)
100 degrees Celsius (10 oC)
0 degrees Celsius (0 oC)
1 gram per cubic centimetre (1g/cm3)
5kg*
0.1mm*
*These are approximate figures
Science Dictionary April 2014
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APPENDIX 2
Circuit Symbols which may be used in Common Entrance papers
Science Dictionary April 2014
Page 31.
AND circuit
Truth tables
INPUTS
OUTPUT
Switch A
0
Switch B
0
Lamp
0
1
0
0
0
1
0
1
1
1
INPUTS
OUTPUT
Switch A
Switch B
Lamp
OFF
OFF
OFF
ON
OFF
OFF
ON
OFF
OFF
ON
ON
ONN
OR circuit
Truth tables
INPUTS
OUTPUT
Switch A
0
Switch B
0
Lamp
0
1
0
1
0
1
1
1
1
1
INPUTS
Science Dictionary April 2014
OUTPUT
Switch A
Switch B
Lamp
OFF
OFF
OFF
ON
OFF
ON
ON
OFF
ON
ON
ON
ON
Page 32.