|
Meanings of the Terms/Words which are used in General Science Grade VI, VII and VIII
|
|
|
Term/Word
|
Meaning
|
|
Glossary
|
A list of terms in a special subject, field, or area of usage.
|
|
Acid
|
A compound containing hydrogen which dissolves in water to produce hydrogen ions (H+) in the solution.
|
|
Acid rain
|
Rain water which is more acidic than usual. Rain water normally has a pH between 5 & 6 but acid rains have pH below 5
|
|
Acidic salts
|
Salt obtained as a result of reaction between strong acid & weak base (Na2 CO3)
|
|
Aerosol
|
A pressurized container used to spray liquids, like paint, in a fine mist
|
|
Alkali
|
A base which dissolves in water is an alkali
|
|
Alveolus
|
An air sac found in the ling which is adapted for gaseous exchange
|
|
Ammeter
|
An instrument for measuring electric current
|
|
Antibiotics
|
Chemicals used to treat many infectious diseases caused by microorganisms such as bacteria
|
|
Apparent brightness
|
How bright a star looks to observes on earth
|
|
A sexual reproduction
|
Reproduction that doesn’t involve the fusion of two gametes
|
|
Asteroids
|
Large lumps of rock and metal that orbit the sun in a region called the asteroid belt between mars and Jupiter
|
|
Astronomer
|
A scientist who studies the stars, planets, and other objects in space
|
|
Astronomy
|
The scientific study of the objects in space such as stars, asteroids and planets
|
|
Astrophysics
|
The science of the physical and chemical aspects of heavenly bodies
|
|
Atmosphere
|
The blanket of gases that surrounds the earth
|
|
Atmospheric pressure
|
The pressure caused by the weight of the air pressing down on the earth’s surface
|
|
Atom
|
This is a basic of matter which can’t be further divided
|
|
Basic salts
|
Salt obtained as a result of reaction between strong base and weak acid (NaHCO3)
|
|
Big bang
|
A tremendous explosion on the beginning of the universe
|
|
Big bang theory
|
The idea that all the matter in the universe came into being with a massive explosion known as the big bang
|
|
Biotechnology
|
The use of biological process from microorganisms to make substances (e.g. penicillin) or to provide services for human beings
|
|
Black hole
|
What is left when a very massive star collapses at the end of its life. A black hole’s gravity is so strong that nothing can escape, not even light
|
|
Breathing
|
The process that brings about an exchange of gases between the organisms and the environment
|
|
Bronchiole
|
One of the many tiny tubes which carries air to end from the alveoli in the lungs
|
|
Bronchitis
|
A lung disease in which the cells lining the bronchi and bronchioles are inflamed
|
|
Cancer
|
A disease in which body’s cell start to divide and multiply in an uncontrolled and disorderly fashion
|
|
Chemical Reaction
|
A change in which one or more chemical elements or compounds(reactants) form new compounds(the products)
|
|
Chemistry
|
The scientific study of all substances and how they react and combine
|
|
Chlorophyll
|
A green pigment found in most plants. It absorbs light energy during photosynthesis
|
|
Chromosome
|
A thread-like structure present in the nucleus of a cell. It contains hereditary materials called genes
|
|
Colloid
|
A mixture of extremely small particles of a substance dispersed in another in which it doesn’t dissolve. The particles are smaller than in a suspension
|
|
Comet
|
An icy jump of material that moves around the sun in a highly elliptical orbit, its ‘tail’ is a thin stream of gas and dust that reflects sunlight
|
|
Compound
|
It consists of two or more elements chemically combined together
|
|
Constellation
|
Stars that appear to form a group with a definite pattern or arrangement, when viewed from the earth
|
|
Current electricity
|
The type of electricity that can flow through wires
|
|
Decanting
|
Process of separating a liquid from a solid that has settled by pouring the liquid carefully out of the container
|
|
Deforestation
|
Destruction of forests due to human activities
|
|
Detergents
|
Substances which when added to water, enable it to remove dirt
|
|
Diaphragm
|
A muscular from the abdomen,’ sheet that separates the chest
|
|
Distillation
|
The process of separating a mixture of liquids, or a liquid from an impurity, by heating. The vapor of the liquid with the lowest boiling point comes off first and is condensed back to a liquid in the condenser
|
|
DNA
|
(Deoxyribonucleic acid) Hereditary material of the cell
|
|
Dwarf star
|
A very small star that may be no larger than earth
|
|
Dynamo
|
A type of generator that produces direct current
|
|
Eclipse
|
The total or partial disappearance of a heavenly body when another one moves between it and the viewer
|
|
Effector
|
A muscle that respond to a message and reacts accordingly
|
|
Electric charge
|
Something that has an electric charge carries electricity. There are two types of electric charge, called positive and negative
|
|
Electric circuit
|
The path along which an electric current flows
|
|
Electric current
|
The flow of positive or negative electric charges
|
|
Electric field
|
The area in which an electric force has an effect
|
|
Electric motor
|
A device that changes electrical energy into movement
|
|
Electric shock
|
The effects on the human body caused by electric current from batteries
|
|
Electricity
|
The effect caused by the presence or movement of electrically charged particles
|
|
Electrolysis
|
Chemical reactions produced by passing electric current
|
|
Electrolytes
|
Electrolytes are chemical compounds, that help electric current to pass through them on ionization (e.g., Na CI, H2SO4)
|
|
Element
|
It is a pure substance which contains same type of elements
|
|
Endothermic reaction
|
A chemical reaction that takes heat from its surroundings
|
|
Evaporation
|
A change of state from liquid to gaseous (vapor), due to the escape of molecules from the surface. A liquid which readily evaporates is described as volatile
|
|
Evening star
|
Another name for the planet Venus, as it appears just after sunset
|
|
Exothermic reaction
|
A chemical reaction that releases heat into its surroundings
|
|
Filtering
|
The process of separating a liquid and a solid by pouring the mixture through a fine mesh (filter paper). The filter paper only lets liquid through PTO
|
|
Galaxy
|
A large group of stars, gas and dust
|
|
Galvanometer
|
An instrument for detecting or measuring very small electric currents
|
|
Gamete
|
A reproductive cell containing the haploid number of chromosomes
|
|
Genes
|
Units controlling inheritance and expression of characters
|
|
Genetic engineering
|
A technique used to transfer genes from one organism to another
|
|
Genotype
|
The genetic combination in an individual
|
|
Generator
|
A machine that turns the energy of movement, or kinetic energy into electrical energy
|
|
Guard cells
|
A pair of special cells present around opening (stomata) in the epidermis of a leaf that regulate the opening and closing of stomata
|
|
Hereditary characters
|
Characteristics which are inherited
|
|
Heredity
|
Transfer of characters from parents to their offspring
|
|
Indicators
|
A chemical compound that changes its color when an acid or an alkali is added into it
|
|
Insulation
|
A material that reduces heat transfer
|
|
Irregular galaxy
|
A galaxy with no definite shape or arrangement
|
|
Kilogram (kg)
|
Units of mass
|
|
Lens
|
A piece of transparent substance with curved surfaces, that makes light bend in a certain way
|
|
Light-year
|
The distance light travels in one year, or 9.5 trillion kilometers
|
|
Luminous
|
The term that describes any object that gives off light
|
|
Mass
|
The amount of matter that is in an object
|
|
Mesophyll
|
Cells found between upper and lower epidermis in a leaf. These cells contain chloroplasts
|
|
Meter (or shooting star)
|
A meteoroid that starts to burn up as it enters the atmosphere
|
|
Meteorite
|
Fragments of rocks striking the surface of the earth. The remains of a meteor that has survived the atmosphere and landed on earth
|
|
Meteoroid
|
A small piece of space debris
|
|
Meteoroids
|
Rocks or fragments of rocks and iron travelling in space
|
|
Meter (m)
|
Unit of length. 1000 meters equals 1 kilometer (km)
|
|
Milky way
|
A spiral galaxy to which out sun and the planets belong. The galaxy in which our solar system lies
|
|
Milky way galaxy
|
Such a galaxy containing solar system
|
|
Mineral acid
|
An acid which is produced chemically from a mineral e.g. hydrochloric acid is produced from sodium chloride and sulphuric acid is produced from sulpher
|
|
Mixture
|
It is formed by the combination of two substances in such a way that no new substance is formed
|
|
Model
|
A representation of something that can’t be seen easily or directly
|
|
molecule
|
It is formed by the combination of same or different atoms
|
|
Motor neurons
|
A nerve cell that transmits impulses to an effector
|
|
Nebula
|
Gigantic clouds of dust and gases in space
|
|
Nerve
|
A collection of nerve fibers
|
|
Nerve fiber
|
A long cytoplasmic extension of a cell body of a neuron. It serves to transmit impulses
|
|
Neuron
|
A nerve cell
|
|
Neutron star
|
A star whose core contains neutrons only
|
|
Non-luminous
|
Describes an object that doesn’t give out light of its own
|
|
Optical microscope
|
An instrument that uses lenses to make small objects look bigger
|
|
Optical telescope
|
An instrument that uses lenses and mirrors to make distant objects look closer
|
|
Orbit
|
The path in which one heavenly body moves around another
|
|
Organic acid
|
An organic compound that is acidic in nature. The most common ones are carboxylic acid (e.g., oxalic acid, formic acid, acetic acid)
|
|
Palisade tissues
|
Cylindrical cells arranged closely and vertically in the upper layer of mesophyll. These cells contain numerous chloroplasts which facilitate the absorption of sunlight
|
|
pH
|
Stands for power of hydrogen, a measure of hydrogen ion concentration in a solution
|
|
Pneumatic
|
Powered by the pressure of a gas, usually air
|
|
Pressure
|
A measure of the amount of force applied to a given area
|
|
Receptor
|
Sense organ, cell or nerve endings that detect stimulus
|
|
Recycling
|
Rendering used articles into useful ones
|
|
Reflex action
|
An immediate response to a specific stimulus without conscious control
|
|
Respiration
|
The process by which energy is released from food substances in living cells
|
|
Revolution
|
The movement of one object around another
|
|
Rotation
|
The spinning motion of an object
|
|
Salt
|
A compound formed by the neutralization reaction between acid & base
|
|
Satellite
|
Bodies that rotate in orbits around other bodies of greater mass under the influence of a gravitational field. For example, the moon is a natural satellite of the earth. Satellites which are used for relying radio, television and telephone signals around the earth are artificial earth satellites. They are called communication satellites.
|
|
Second (s)
|
Unit of time. A second is a duration in which the cesium -133 atom completes 9,192,631,770 vibrations under specified conditions
|
|
Selective breeding
|
Technology using breeding of selected organisms
|
|
Sexual reproduction
|
Reproduction that involves the fusion of two reproductive cells called gametes
|
|
SI units
|
An internationally agreed system of standard units used for scientific measurements
|
|
Soap
|
It is the sodium or potassium salt of a long-chain carboxylic acid. It is made by reacting animal fats or vegetable oils with Na OH or KOH. The process of making soap is called saponification
|
|
Solar system
|
The sun together with all of the planets and other objects orbiting it
|
|
Solar wind
|
A constant stream of invisible particles blow out into space from the sun
|
|
Space probe
|
Unmanned spacecraft sent to explore the solar system and beyond
|
|
Space shuttle
|
A reusable manned spacecraft that is launched like a rocket, but lands on reentry like plane
|
|
Space station
|
A large satellite orbiting the earth where astronauts can live and perform scientific research over fairly long period
|
|
Stars
|
Shinning objects of gases in nebula
|
|
Sun
|
This is a star
|
|
Supergiant
|
An extremely large star
|
|
Suspension
|
Fine particles of a solid suspended in a liquid in which the solid doesn’t dissolve
|
|
True brightness
|
The actual amount of energy in the form of light that is released by a star
|
|
Universe (for cosmos)
|
The collection of all matter, energy and space that exists
|
|
Universe theory
|
The idea that the universe expands and shrinks, in a repeating cycle of big bangs and big crunches
|
|
Vacuum
|
An empty space where there are no particles of air or other matter
|
|
Variable resister (or rheostat)
|
An electronic component that can be adjusted to give different amounts of resistance
|
|
Variable star
|
A star that changes gradually in brilliance
|
|
Variation
|
The differences that can be observed within a species
|
|
Voluntary action
|
An action that is controlled by the will
|
|
Volume
|
The amount of space something takes up. It is measured in cubic meters (m3). A smaller unit of volume is the cubic centimeter (cm3), o0 milliliter (ml). 1 cm3= 1 ml=1/1000000m3
|
|
Weather forecast
|
A prediction of what the weather will be for some time in the future
|
|
Weight
|
The measure of the force of gravity acting on an object
|
|
X-Rays
|
Wavelength, high-frequency electromagnetic waves that can pass through most soft substances but no hard, dense ones
|
|
zygote
|
A cell formed as a result of the fusion of the sperm and the ovum. It divides repeatedly and becomes the embryo
|
|
|
Top site ,.. amazaing post ! Just keep the work on !