Glossary

Every term from the notes of all 21 chapters, in alphabetical order. Each meaning carries its textbook page.

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5R: Refuse, Reduce, Reuse, Recycle and Recovery; it replaced the 3R concept to achieve zero waste. p. 61 Form 4 · Chapter 4: Green Technology for Environmental Sustainability

A

Acceleration: The rate of change of velocity. p. 230 Form 4 · Chapter 11: Force and Motion
Acid rain: Rain caused by dangerous gases emitted from vehicles; it destroys plants, corrodes buildings and irons, and damages tyres. p. 66 Form 4 · Chapter 4: Green Technology for Environmental Sustainability
Active ingredient: A specific component of a product that has effects on the cure or prevention of disease. p. 217 Form 4 · Chapter 10: Chemicals in Medicine and Health
Acupuncture: Inserting sterile needles at acupuncture points to stimulate the nervous system to relieve pain. p. 208 Form 4 · Chapter 10: Chemicals in Medicine and Health
Adrenaline: Adrenal hormone that prepares the body for an emergency. p. 148 Form 4 · Chapter 7: Body Coordination
Aerenchyma tissue: Thin-walled cells forming air spaces in aquatic plants, which help buoyancy. p. 135 Form 4 · Chapter 6: Support, Movement and Growth
Alcohol: An organic carbon compound which contains carbon, hydrogen and oxygen elements. p. 150 Form 5 · Chapter 5: Carbon Compounds
Alkane: A saturated hydrocarbon in which each carbon atom forms single covalent bonds with other carbon atoms. p. 148 Form 5 · Chapter 5: Carbon Compounds
Alkene: An unsaturated hydrocarbon with at least one double covalent bond between two carbon atoms. p. 148 Form 5 · Chapter 5: Carbon Compounds
Allele: The pair of genes at the same locus (position) on homologous chromosomes; dominant or recessive. p. 84 Form 4 · Chapter 5: Genetics
Alloy: A mixture of several types of metals, or of metal and non-metal, by a certain percentage. p. 184 Form 4 · Chapter 9: Chemicals in Industry
Alternative energy source: A source of energy that will not deplete easily, such as nuclear energy or renewable energy sources. p. 149 Form 5 · Chapter 5: Carbon Compounds
Amniocentesis: A method to identify foetal cell abnormalities from the 15th to the 20th week of pregnancy. p. 96 Form 4 · Chapter 5: Genetics
Analgesic: Modern medicine that relieves pain, such as aspirin, paracetamol and codeine. p. 207 Form 4 · Chapter 10: Chemicals in Medicine and Health
Anode: The electrode connected to the positive terminal of an electrical source. p. 179 Form 5 · Chapter 6: Electrochemistry
Antagonistic muscles: A pair of skeletal muscles that act in opposite directions to one another. p. 128 Form 4 · Chapter 6: Support, Movement and Growth
Antibiotic: Modern medicine that kills or inhibits infectious bacteria, such as penicillin and streptomycin. p. 207 Form 4 · Chapter 10: Chemicals in Medicine and Health
Antibiotic: Medicine used to treat infections caused by bacteria. p. 36 Form 5 · Chapter 1: Microorganisms
Antibiotic resistance: When an antibiotic loses its ability to kill bacteria. p. 36 Form 5 · Chapter 1: Microorganisms
Antioxidants: Chemical substances that slow down or stop the oxidation process and protect cells from free radicals. p. 214 Form 4 · Chapter 10: Chemicals in Medicine and Health
Antiseptic: A chemical substance applied on human skin or wounds to prevent pathogenic infections. p. 35 Form 5 · Chapter 1: Microorganisms
Apogee: The position of a satellite in an elliptical orbit which is furthest from the planet or star it encircles. p. 237 Form 5 · Chapter 9: Space Technology
Appendicular skeleton: The pectoral girdle, the upper limbs, the pelvic girdle and the lower limbs. p. 122 Form 4 · Chapter 6: Support, Movement and Growth
Aseptic technique: A healthcare procedure carried out to prevent infections caused by pathogens or to remove existing pathogens. p. 33 Form 5 · Chapter 1: Microorganisms
Atherosclerosis: A condition in which cholesterol deposited on the inner artery walls narrows the lumen and disrupts or blocks blood flow. p. 159 Form 5 · Chapter 5: Carbon Compounds
Atom: The smallest particle of an element; the most basic unit in an element. p. 168 Form 4 · Chapter 8: Elements and Substances
Atomic substance: A substance that contains only atoms, such as metals and inert gases. p. 168 Form 4 · Chapter 8: Elements and Substances
Autosomes: Chromosomes carrying genes for characteristics such as eye colour, tongue rolling and hair type. p. 78 Form 4 · Chapter 5: Genetics
Average rate of reaction: The average value for the rate of reaction that occurs in a specific time interval. p. 119 Form 5 · Chapter 4: Rate of Reaction
Axial skeleton: The skull, the vertebral column, the sternum and the ribs. p. 122 Form 4 · Chapter 6: Support, Movement and Growth

B

Bernoulli's principle: A fluid moving at a higher velocity produces a lower pressure in that region. p. 228 Form 5 · Chapter 8: Force and Pressure
Binary fission: Asexual reproduction in which the nucleus divides, then the cytoplasm, forming two daughter cells. p. 11 Form 5 · Chapter 1: Microorganisms
Biochemical Oxygen Demand (BOD): The amount of dissolved oxygen needed by microorganisms such as bacteria to decompose organic substances in a water resource. p. 102 Form 5 · Chapter 3: Sustainability of the Environment
Biofuel: Fatty acid methyl ester that is produced from plant oils and animal fats. p. 67 Form 4 · Chapter 4: Green Technology for Environmental Sustainability
Biological control: A method that uses interactions between organisms, such as prey-predator and parasitism, to control crop pests. p. 74 Form 5 · Chapter 2: Nutrition and Food Technology
Blood pressure: The pressure applied by the blood on the walls of the blood vessels during blood circulation. p. 41 Form 4 · Chapter 3: Techniques of Measuring the Parameters of Body Health
Body Mass Index (BMI): The measurement of body mass against height. p. 43 Form 4 · Chapter 3: Techniques of Measuring the Parameters of Body Health
Bomb calorimeter: A special apparatus used to measure the calorific value of food. p. 50 Form 5 · Chapter 2: Nutrition and Food Technology
Boron control rods: Control the rate of nuclear fission by absorbing surplus neutrons. p. 260 Form 4 · Chapter 12: Nuclear Energy
Brass: Alloy of copper 75% and zinc 25%; strong, shiny, malleable and gold in colour. p. 184 Form 4 · Chapter 9: Chemicals in Industry
Bronze: Alloy of copper 88% and tin 12%; hard, resistant to corrosion, attractive colour. p. 184 Form 4 · Chapter 9: Chemicals in Industry
Budding: Asexual reproduction of unicellular fungi such as yeast. p. 7 Form 5 · Chapter 1: Microorganisms

C

Calorific value: The amount of energy released from the complete oxidation or combustion of 1 g of food. p. 50 Form 5 · Chapter 2: Nutrition and Food Technology
Capsid: The protein layer that protects a virus's nucleic acid and determines its shape. p. 14 Form 5 · Chapter 1: Microorganisms
Carbon compound: A compound which contains the element carbon, C. p. 142 Form 5 · Chapter 5: Carbon Compounds
Carbon cycle: The way carbon elements are recycled through the formation or decomposition of carbon compounds by respiration, combustion, decomposition and photosynthesis. p. 142 Form 5 · Chapter 5: Carbon Compounds
Carbon footprint: The amount of greenhouse gas, such as carbon dioxide, released into the atmosphere as a result of human activities such as open burning and burning of fossil fuels. p. 68 Form 4 · Chapter 4: Green Technology for Environmental Sustainability
Carbon footprint: The total amount of carbon dioxide released into the atmosphere as a result of the activities of an individual, event, organisation, community or products. p. 92 Form 5 · Chapter 3: Sustainability of the Environment
Carbon handprint: Steps that reduce a product's carbon footprint and increase its positive impacts on environmental sustainability. p. 94 Form 5 · Chapter 3: Sustainability of the Environment
Carbon sink: A natural place such as a forest or ocean that removes carbon dioxide from the air. p. 95 Form 5 · Chapter 3: Sustainability of the Environment
Cardiopulmonary resuscitation: CPR: an emergency aid that combines chest compressions and breathing into the mouth of the victim to restore their heartbeat and breathing. p. 20 Form 4 · Chapter 2: Emergency Help
Cartilage: Tissue that acts as a cushion, protects the joint and reduces friction. p. 129 Form 4 · Chapter 6: Support, Movement and Growth
Catalyst: A substance that increases the rate of reaction when used in a reaction. p. 125 Form 5 · Chapter 4: Rate of Reaction
Cathode: The electrode connected to the negative terminal of an electrical source. p. 179 Form 5 · Chapter 6: Electrochemistry
Ceramic: A non-metal substance formed by heat at a very high temperature, made from clay. p. 190 Form 4 · Chapter 9: Chemicals in Industry
Chaetae: Bristles at the side of the earthworm's body that help it move on land. p. 118 Form 4 · Chapter 6: Support, Movement and Growth
Chain reaction: Continuous fission as neutrons bombard and split new nuclei of large mass. p. 258 Form 4 · Chapter 12: Nuclear Energy
Chemical reaction: A process in which one or more reactants are converted to one or more products. p. 116 Form 5 · Chapter 4: Rate of Reaction
Chest compressions: Pressing on the centre of the victim's chest to restore blood circulation in the victim's body. p. 23 Form 4 · Chapter 2: Emergency Help
Chiropractic: Adjusting bone position with the hands, without medicine. p. 208 Form 4 · Chapter 10: Chemicals in Medicine and Health
Chlorosis: Leaves that are pale green or yellow because they lack chlorophyll. p. 59 Form 5 · Chapter 2: Nutrition and Food Technology
Choking: A situation that happens when the respiratory tract is blocked because of food or a foreign object. p. 25 Form 4 · Chapter 2: Emergency Help
Chromosome: A fine thread-like structure made of nucleic acids and protein, found in the nucleus; it contains a long DNA molecule. p. 76 Form 4 · Chapter 5: Genetics
Complementary medicine: Health care methods from many cultural backgrounds, covering natural products and mind and body practices. p. 205 Form 4 · Chapter 10: Chemicals in Medicine and Health
Concrete shield: Prevents radioactive radiation leakage from the reactor. p. 260 Form 4 · Chapter 12: Nuclear Energy
Conjugation: Sexual reproduction in which two cells unite and exchange genetic material. p. 11 Form 5 · Chapter 1: Microorganisms
Contact Process: The industrial process that produces sulphuric acid through sulphur dioxide, sulphur trioxide and oleum. p. 135 Form 5 · Chapter 4: Rate of Reaction
Converging lens: A convex lens, because light rays converge after passing through it. p. 202 Form 5 · Chapter 7: Light and Optics
Cradle-to-cradle life cycle: A product's life cycle from source to disposal through recycling. p. 96 Form 5 · Chapter 3: Sustainability of the Environment
Cradle-to-grave life cycle: A product's life cycle from source to disposal through decay. p. 96 Form 5 · Chapter 3: Sustainability of the Environment

D

DD: Decimal degree, the other format for writing GPS coordinates. p. 244 Form 5 · Chapter 9: Space Technology
Deceleration: Decrease in velocity, such as when a bicycle's brakes are applied. p. 230 Form 4 · Chapter 11: Force and Motion
Denitrification: Denitrifying bacteria convert nitrate ions in the soil into nitrogen, which returns to the air. p. 64 Form 5 · Chapter 2: Nutrition and Food Technology
Depolymerisation: Splitting a long-chain polymer into its monomers through chemical reactions. p. 193 Form 4 · Chapter 9: Chemicals in Industry
Diabetes insipidus: Disease from ADH deficiency: poor water reabsorption, excessive urine and thirst. p. 151 Form 4 · Chapter 7: Body Coordination
Diabetes mellitus: Disease from insulin deficiency: excess glucose is not converted to glycogen, so blood glucose rises. p. 151 Form 4 · Chapter 7: Body Coordination
Diastolic pressure: The bottom number of a blood pressure reading; the pressure on the wall of blood vessels when the heart muscle is resting (between heartbeats). p. 41 Form 4 · Chapter 3: Techniques of Measuring the Parameters of Body Health
Disc brake: The front-wheel brake in which the brake pad is pressed onto a steel plate. p. 226 Form 5 · Chapter 8: Force and Pressure
Disinfectant: A chemical substance used on non-living things to kill microorganisms, especially pathogens. p. 35 Form 5 · Chapter 1: Microorganisms
Displacement: The distance of the shortest path that connects two locations in a specified direction. p. 226 Form 4 · Chapter 11: Force and Motion
Distance: The total path length travelled by an object. p. 226 Form 4 · Chapter 11: Force and Motion
Diverging lens: A concave lens, because light rays diverge after passing through it. p. 202 Form 5 · Chapter 7: Light and Optics
DMS: Degrees, minutes and seconds, one format for writing GPS coordinates. p. 244 Form 5 · Chapter 9: Space Technology
DNA: Deoxyribonucleic acid, made of nucleotides; two antiparallel polynucleotide chains twisted into a double helix. p. 77 Form 4 · Chapter 5: Genetics
Drugs: Chemical substances that can disrupt neuron function by delaying impulse transmission. p. 152 Form 4 · Chapter 7: Body Coordination
Drum brake: The back-wheel brake in which the brake shoe presses the brake lining onto the brake drum. p. 226 Form 5 · Chapter 8: Force and Pressure
Duplet electron arrangement: The stable electron arrangement with 2 electrons in the first shell. p. 173 Form 4 · Chapter 8: Elements and Substances
Duralumin: Alloy of aluminium 95%, copper 3%, magnesium 1% and manganese 1%; light, strong, resistant to corrosion. p. 184 Form 4 · Chapter 9: Chemicals in Industry

E

Ecdysis: The process of shedding the exoskeleton. p. 116 Form 4 · Chapter 6: Support, Movement and Growth
Eco currency: A proposed universal currency used as a medium of exchange to help maintain environmental balance. p. 106 Form 5 · Chapter 3: Sustainability of the Environment
Eco enzyme: A natural product obtained from the fermentation of agricultural waste such as fruit or vegetable waste. p. 30 Form 5 · Chapter 1: Microorganisms
Effective microorganisms (EM): A mix of lactic acid bacteria, photosynthetic bacteria and yeast used to treat polluted water. p. 104 Form 5 · Chapter 3: Sustainability of the Environment
Electrochemical series: An arrangement of metals according to the tendency of their atoms to donate electrons. p. 183 Form 5 · Chapter 6: Electrochemistry
Electrochemistry: The study of the relationship between electrical and chemical phenomena, such as those in electrolytic cells and chemical cells. p. 178 Form 5 · Chapter 6: Electrochemistry
Electrocoagulation: A technique to treat wastewater that applies electrolysis and coagulation. p. 191 Form 5 · Chapter 6: Electrochemistry
Electrolysis: The decomposition of a compound in the molten or aqueous state into its constituent elements when electric current flows through it. p. 178 Form 5 · Chapter 6: Electrochemistry
Electrolyte: A substance in the molten or aqueous state which allows electric current to flow through it and undergoes chemical changes. p. 179 Form 5 · Chapter 6: Electrochemistry
Electron arrangement: How electrons are arranged in shells around the nucleus, written like 2.8.6 for sulphur. p. 172 Form 4 · Chapter 8: Elements and Substances
Electroplating: Coating other metals with gold, platinum or silver by electrolysis to look more attractive and withstand corrosion. p. 191 Form 5 · Chapter 6: Electrochemistry
Emulsification: The process where palm oil is broken into smaller droplets, increasing its total surface area. p. 165 Form 5 · Chapter 5: Carbon Compounds
Enclosed system: A physical system where matter cannot enter or leave the system. p. 222 Form 5 · Chapter 8: Force and Pressure
Endocrine glands: Ductless glands that secrete hormones directly into the blood circulatory system. p. 144 Form 4 · Chapter 7: Body Coordination
Endocrine system: A body system that coordinates body functions involving chemical substances (hormones). p. 144 Form 4 · Chapter 7: Body Coordination
Endoskeleton: Support for all vertebrates including humans, made of internal bones and cartilage. p. 114 Form 4 · Chapter 6: Support, Movement and Growth
Endospore: A spore with a strong protective coat formed in bacterial cells to withstand extreme surroundings. p. 13 Form 5 · Chapter 1: Microorganisms
Energy efficiency: The use of less energy to carry out work at the same or higher rate without affecting the production and the quality of the desired outcome. p. 53 Form 4 · Chapter 4: Green Technology for Environmental Sustainability
Environmental pollution: Unwanted changes in the physical, chemical or biological characteristics of air, water and soil. p. 99 Form 5 · Chapter 3: Sustainability of the Environment
Epiglottis: Folds and blocks the respiratory tract (trachea) when someone swallows food. p. 25 Form 4 · Chapter 2: Emergency Help
Eutrophication: The ecosystem response to an increase of phosphate ions and nitrate ions in an aquatic ecosystem, such as rapid algae growth. p. 101 Form 5 · Chapter 3: Sustainability of the Environment
Exoskeleton: Support for most invertebrates: an outer layer of waxy chitin or shell. p. 114 Form 4 · Chapter 6: Support, Movement and Growth
Expendable launch vehicle (ELV): A launch vehicle which is used only once. p. 239 Form 5 · Chapter 9: Space Technology
Eyewash station: Used to immediately rinse and wash the eye that has come into contact with chemical substances. p. 5 Form 4 · Chapter 1: Safety Measures in the Laboratory

F

Fermentation: The breakdown of complex substances into simpler substances by bacteria, yeast or other useful microorganisms. p. 76 Form 5 · Chapter 2: Nutrition and Food Technology
Fermentation: The process in which the zymase in yeast converts glucose into ethanol and carbon dioxide. p. 151 Form 5 · Chapter 5: Carbon Compounds
Fire extinguisher: A device that is used to control or extinguish fire. p. 10 Form 4 · Chapter 1: Safety Measures in the Laboratory
Focal length: The distance between the focal point and the optical centre. p. 205 Form 5 · Chapter 7: Light and Optics
Focal point: The point on the principal axis where rays parallel to the principal axis converge (convex lens) or appear to diverge from (concave lens). p. 205 Form 5 · Chapter 7: Light and Optics
Foetal alcohol syndrome: Defects in a baby whose mother consumed excessive alcohol, such as a small head and brain, abnormal face and stunted growth. p. 156 Form 5 · Chapter 5: Carbon Compounds
Fractional distillation: The process that separates petroleum into fractions with different boiling points. p. 146 Form 5 · Chapter 5: Carbon Compounds
Free fall: Falling due to the effects of gravitational force only. p. 241 Form 4 · Chapter 11: Force and Motion
Free radicals: Atoms or molecules that lack one electron, so they are unstable, reactive and attack other atoms or molecules. p. 212 Form 4 · Chapter 10: Chemicals in Medicine and Health
Fume chamber: Used to carry out experiments that use substances which are volatile, flammable, poisonous, corrosive or pungent. p. 5 Form 4 · Chapter 1: Safety Measures in the Laboratory

G

Gene: A basic hereditary unit that determines an individual's characteristics; genes are segments of DNA along the chromosomes. p. 77 Form 4 · Chapter 5: Genetics
Gene therapy: An experimental technique that introduces a normal gene into a patient's cells to replace defective genes. p. 98 Form 4 · Chapter 5: Genetics
Genetic effects: Effects of radiation such as deformation in babies, cell mutation and cancer. p. 265 Form 4 · Chapter 12: Nuclear Energy
Genetics: The study of genes, heredity and variations in organisms. p. 77 Form 4 · Chapter 5: Genetics
Genotype: The genetic information in an organism. p. 86 Form 4 · Chapter 5: Genetics
Geostationary Orbit (GEO): An orbit at 35 786 km with the equatorial plane as its orbital plane. p. 236 Form 5 · Chapter 9: Space Technology
Geosynchronous Orbit (GSO): An orbit at 35 786 km whose orbital plane is at an inclined angle to the equatorial plane. p. 236 Form 5 · Chapter 9: Space Technology
Global Positioning System (GPS): A navigation system which gives information on location and time to its users in all weather conditions. p. 243 Form 5 · Chapter 9: Space Technology
GMO: Genetically Modified Organism: a plant, animal, bacteria or virus genetically modified for a particular purpose. p. 101 Form 4 · Chapter 5: Genetics
Goitre: Swelling of the thyroid; one effect of thyroxine deficiency. p. 150 Form 4 · Chapter 7: Body Coordination
Graphite moderator: Slows down the neutrons in a reactor. p. 260 Form 4 · Chapter 12: Nuclear Energy
Gravitational acceleration: The acceleration of an object falling due to Earth's gravitational force, symbol g. p. 239 Form 4 · Chapter 11: Force and Motion
Green Building Index (GBI): One of Malaysia's energy efficiency initiatives. p. 53 Form 4 · Chapter 4: Green Technology for Environmental Sustainability
Green Technology: The development and application of products, equipment and systems used to conserve the environment and nature, as well as minimising and reducing the negative effects of human activities. p. 52 Form 4 · Chapter 4: Green Technology for Environmental Sustainability
Green transportation: Any form of transportation that releases very minimal greenhouse gases or none at all. p. 66 Form 4 · Chapter 4: Green Technology for Environmental Sustainability
Group: A vertical column in the Modern Periodic Table of Elements; there are 18 groups. p. 171 Form 4 · Chapter 8: Elements and Substances
Growth curve: A graph of growth unit (height, volume, wet mass or dry mass) against time. p. 115 Form 4 · Chapter 6: Support, Movement and Growth

H

Haber Process: The industrial process that produces ammonia from nitrogen and hydrogen over iron filings. p. 135 Form 5 · Chapter 4: Rate of Reaction
Health food: A natural food substance in a normal diet that maintains health and does not contain chemical substances. p. 83 Form 5 · Chapter 2: Nutrition and Food Technology
Health supplement: Nutrients taken as a capsule, pill, liquid or powder in pre-determined doses. p. 83 Form 5 · Chapter 2: Nutrition and Food Technology
Heimlich Manoeuvre: An emergency procedure that is carried out to save an individual who is choking. p. 25 Form 4 · Chapter 2: Emergency Help
High Earth Orbit (HEO): A satellite orbit with an orbital height equal to or exceeding 35 780 km. p. 236 Form 5 · Chapter 9: Space Technology
Hohmann transfer orbit: An orbit used to move a satellite from a small orbit to a large orbit, with burning at perigee and burning at apogee. p. 239 Form 5 · Chapter 9: Space Technology
Homeopathy: Medicine given by symptoms that strengthens the body's immunity rather than killing germs. p. 209 Form 4 · Chapter 10: Chemicals in Medicine and Health
Homeostasis: A mechanism that regulates body temperature so that it remains in a balanced and stable state. p. 36 Form 4 · Chapter 3: Techniques of Measuring the Parameters of Body Health
Homologous chromosomes: A pair of chromosomes of similar shape and size. p. 78 Form 4 · Chapter 5: Genetics
Homologous series: A specific group of organic compounds which have similar chemical properties, such as the alkanes and the alkenes. p. 148 Form 5 · Chapter 5: Carbon Compounds
Hormonal imbalance: Over secretion or under secretion of a hormone by an endocrine gland. p. 149 Form 4 · Chapter 7: Body Coordination
Hormone: A chemical substance secreted by endocrine glands and carried in the blood to target organs. p. 144 Form 4 · Chapter 7: Body Coordination
Hydraulic jack: A device that uses a hydraulic system to lift heavy loads such as cars in workshops. p. 224 Form 5 · Chapter 8: Force and Pressure
Hydraulic system: A system of two pistons of different surface areas joined by water or oil, used to produce a large output force. p. 223 Form 5 · Chapter 8: Force and Pressure
Hydrocarbon: An organic carbon compound made up of only carbon and hydrogen elements. p. 145 Form 5 · Chapter 5: Carbon Compounds
Hydrolysis: The reaction of palm oil with water to produce glycerol and fatty acids. p. 165 Form 5 · Chapter 5: Carbon Compounds
Hydrophilic: The 'head' part of a soap molecule, made up of an ionic group, which can dissolve in water. p. 168 Form 5 · Chapter 5: Carbon Compounds
Hydrophobic: The 'tail' part of a soap molecule, a hydrocarbon chain, which dissolves in oil or grease but not in water. p. 168 Form 5 · Chapter 5: Carbon Compounds
Hydrostatic skeleton: A muscular wall enclosing a fluid-filled body cavity, in soft-bodied invertebrates such as worms. p. 115 Form 4 · Chapter 6: Support, Movement and Growth

I

Image distance: The distance between the image and the optical centre, v. p. 205 Form 5 · Chapter 7: Light and Optics
Inertia: The natural tendency of an object to resist any change in its original state, at rest or in motion. p. 246 Form 4 · Chapter 11: Force and Motion
Inertial balance: A device invented by NASA to determine the mass of objects in outer space. p. 248 Form 4 · Chapter 11: Force and Motion
Inheritance: The transmission of characteristics from the parents to the children. p. 84 Form 4 · Chapter 5: Genetics
Instantaneous rate of reaction: The rate of reaction at a particular point of time, found from the gradient of the tangent to the curve. p. 121 Form 5 · Chapter 4: Rate of Reaction
Instar: The zero growth stage between moults, shown as the horizontal part of the step-shaped curve. p. 116 Form 4 · Chapter 6: Support, Movement and Growth
Insulin: Pancreas hormone that converts excess glucose into glycogen stored in the liver. p. 148 Form 4 · Chapter 7: Body Coordination
Ion: A positively or negatively charged particle, formed when an atom loses or gains electrons. p. 168 Form 4 · Chapter 8: Elements and Substances
Ionic substance: A substance that contains positive and negative ions, formed when metals react with non-metals. p. 169 Form 4 · Chapter 8: Elements and Substances
Isotopes: Atoms of an element with the same number of protons but a different number of neutrons. p. 175 Form 4 · Chapter 8: Elements and Substances

J

Joint: The meeting place between two or more bones; movable (hinge joint at the elbow) or immovable (skull). p. 128 Form 4 · Chapter 6: Support, Movement and Growth

K

Karyotype: The arrangement of homologous chromosomes according to their shapes and sizes. p. 78 Form 4 · Chapter 5: Genetics

L

Laminar flow cabinet: Used to avoid contamination when microbiological activities are carried out. p. 5 Form 4 · Chapter 1: Safety Measures in the Laboratory
Latex: The milky fluid obtained from tapped rubber trees, processed into natural rubber. p. 194 Form 4 · Chapter 9: Chemicals in Industry
Lens: A transparent medium such as glass which has one or two curved surfaces. p. 202 Form 5 · Chapter 7: Light and Optics
Lift: The upward force on an aeroplane wing, which comes from the aerofoil shape and the angle of attack. p. 229 Form 5 · Chapter 8: Force and Pressure
Ligament: An elastic, flexible and strong connective tissue that joins two bones. p. 129 Form 4 · Chapter 6: Support, Movement and Growth
Lignin: A tough and hard complex substance that builds the woody tissue of woody plants. p. 134 Form 4 · Chapter 6: Support, Movement and Growth
Linear motion: Motion of an object in a straight path. p. 226 Form 4 · Chapter 11: Force and Motion
Liver cirrhosis: Chronic damage, scarring and hardening of the liver so it fails to function normally. p. 156 Form 4 · Chapter 7: Body Coordination
Low Earth Orbit (LEO): A satellite orbit with an orbital height of 180 – 2 000 km. p. 236 Form 5 · Chapter 9: Space Technology

M

Macronutrient: An element (or mineral) required by plants in large quantities. p. 58 Form 5 · Chapter 2: Nutrition and Food Technology
Magnifying power of microscope: The magnifying power of the objective lens multiplied by the magnifying power of the eyepiece. p. 211 Form 5 · Chapter 7: Light and Optics
Malnutrition: A health problem caused by a lack or an excess of any class of food. p. 48 Form 5 · Chapter 2: Nutrition and Food Technology
Mass: The quantity of matter in an object, measured in kilograms (kg). p. 246 Form 4 · Chapter 11: Force and Motion
Medicine: A drug or substance taken to control health, treat or prevent diseases. p. 206 Form 4 · Chapter 10: Chemicals in Medicine and Health
Medium Earth Orbit (MEO): A satellite orbit with an orbital height of 2 000 – 35 780 km. p. 236 Form 5 · Chapter 9: Space Technology
Meiosis: Cell division into four distinct cells, each with half the number of chromosomes of the parent cell; it produces gametes. p. 79 Form 4 · Chapter 5: Genetics
Mercury poisoning: Happens when someone touches mercury or it absorbs through the skin in certain quantities. p. 9 Form 4 · Chapter 1: Safety Measures in the Laboratory
Micronutrient: An element (or mineral) required by plants in small quantities. p. 58 Form 5 · Chapter 2: Nutrition and Food Technology
Microorganism: A minute organism that can only be seen with the help of a microscope. p. 4 Form 5 · Chapter 1: Microorganisms
Microplastics: Plastic pieces less than 5 mm in length that can become hazardous inside aquatic organisms. p. 98 Form 5 · Chapter 3: Sustainability of the Environment
Mind: The brain function relating to consciousness, personality, thinking, memory, judgement, intellect and emotion. p. 158 Form 4 · Chapter 7: Body Coordination
Mitosis: Cell division that forms two identical daughter cells with the same number of chromosomes and genetic content as the parent cell. p. 79 Form 4 · Chapter 5: Genetics
Modern medicine: Medicine combining health science and biomedical fields such as clinical medicine, medical research and surgery. p. 205 Form 4 · Chapter 10: Chemicals in Medicine and Health
Molecular substance: A substance that contains molecules, such as most non-metals and compounds of non-metals. p. 169 Form 4 · Chapter 8: Elements and Substances
Molecule: Two or more atoms chemically combined; the atoms can be the same or different. p. 168 Form 4 · Chapter 8: Elements and Substances
Monohybrid cross: A cross that studies one characteristic at a time, such as height (tall or dwarf). p. 86 Form 4 · Chapter 5: Genetics
Monomer: The smaller molecular unit that makes up a polymer. p. 192 Form 4 · Chapter 9: Chemicals in Industry
Mouth-to-mouth resuscitation: Pinching the victim's nose and blowing air into the victim's mouth for 1 second, so oxygenated air reaches the lungs. p. 23 Form 4 · Chapter 2: Emergency Help
Mutagens: External factors that cause mutation. p. 93 Form 4 · Chapter 5: Genetics
Mutation: A spontaneous and random change in the genes and chromosomes that can change the characteristics of the offspring. p. 90 Form 4 · Chapter 5: Genetics

N

Negative Emission Technologies: Technologies that remove the carbon dioxide content in the atmosphere. p. 106 Form 5 · Chapter 3: Sustainability of the Environment
Nitrate leaching: Nitrate ions in the soil dissolve in water and flow into rivers or underground water. p. 64 Form 5 · Chapter 2: Nutrition and Food Technology
Nitrification: Nitrifying bacteria convert ammonium compounds into nitrite ions and then nitrate ions. p. 63 Form 5 · Chapter 2: Nutrition and Food Technology
Nitrogen cycle: A natural cycle that recycles nitrogen between plants and animals, and the atmosphere, soil and water. p. 62 Form 5 · Chapter 2: Nutrition and Food Technology
Nitrogen fixation: Nitrogen-fixing bacteria convert nitrogen in the air into nitrate ions. p. 63 Form 5 · Chapter 2: Nutrition and Food Technology
Non-electrolyte: A substance which does not allow electric current to flow through it in the molten or aqueous state. p. 179 Form 5 · Chapter 6: Electrochemistry
Normal adjustment: A telescope set with its objective lens and eyepiece fₒ + fₑ apart, so the image is viewed more comfortably. p. 212 Form 5 · Chapter 7: Light and Optics
Normal flora: Microorganisms found in humans and animals which do not cause illness. p. 4 Form 5 · Chapter 1: Microorganisms
Nuclear energy: Energy resulting from reactions in the nucleus of atoms. p. 258 Form 4 · Chapter 12: Nuclear Energy
Nuclear fission: Splitting a heavy radioactive nucleus into two or more lighter, more stable nuclei with the release of energy. p. 258 Form 4 · Chapter 12: Nuclear Energy
Nuclear fusion: Combining two light radioactive nuclei to form a heavier nucleus with the release of energy. p. 259 Form 4 · Chapter 12: Nuclear Energy
Nuclear power station: A station that generates electricity from nuclear energy, consisting of a nuclear reactor and a generator. p. 260 Form 4 · Chapter 12: Nuclear Energy
Nucleon number: The total number of protons and neutrons in the nucleus of an atom. p. 175 Form 4 · Chapter 8: Elements and Substances

O

Object distance: The distance between the object and the optical centre, u. p. 205 Form 5 · Chapter 7: Light and Optics
Octet electron arrangement: The stable electron arrangement with 8 electrons in the outermost shell. p. 173 Form 4 · Chapter 8: Elements and Substances
Oleum: H₂S₂O₇, formed when sulphur trioxide dissolves in concentrated sulphuric acid. p. 136 Form 5 · Chapter 4: Rate of Reaction
Optical centre: The point at the centre of the lens; light rays which pass through it do not refract. p. 205 Form 5 · Chapter 7: Light and Optics
Oxidation: A chemical reaction in which a substance loses electrons. p. 212 Form 4 · Chapter 10: Chemicals in Medicine and Health

P

Pascal's principle: Pressure exerted on a fluid (liquid or gas) in an enclosed system is transmitted uniformly throughout the fluid and in all directions. p. 222 Form 5 · Chapter 8: Force and Pressure
Pasteurisation: Heating a liquid below its boiling point to kill pathogens, then cooling it quickly. p. 77 Form 5 · Chapter 2: Nutrition and Food Technology
Pathogen: A harmful microorganism that can cause diseases. p. 33 Form 5 · Chapter 1: Microorganisms
Perigee: The position of a satellite in an elliptical orbit which is nearest to the planet or star it encircles (Figure 9.3). p. 237 Form 5 · Chapter 9: Space Technology
Period: A horizontal row of elements in the Modern Periodic Table of Elements; there are 7 periods. p. 171 Form 4 · Chapter 8: Elements and Substances
Personal protective equipment: Equipment needed to protect the wearer from danger. p. 4 Form 4 · Chapter 1: Safety Measures in the Laboratory
Pewter: Alloy of tin 96%, copper 3% and antimony 1%; lustrous and resistant to corrosion. p. 184 Form 4 · Chapter 9: Chemicals in Industry
Phenotype: The physical characteristics shown in an organism. p. 86 Form 4 · Chapter 5: Genetics
Photogate: A timing device that accurately measures very fast motion or short time intervals. p. 232 Form 4 · Chapter 11: Force and Motion
Pituitary gland: The master gland below the cerebrum; it secretes ADH and growth hormone. p. 146 Form 4 · Chapter 7: Body Coordination
Plasmid: A small circular chromosome that replicates independently and transfers genetic material during bacterial conjugation. p. 13 Form 5 · Chapter 1: Microorganisms
Polymer: A large molecule formed by chains of smaller molecular units. p. 192 Form 4 · Chapter 9: Chemicals in Industry
Polymerisation: Joining monomers through the formation of chemical bonds to produce a long-chain polymer. p. 193 Form 4 · Chapter 9: Chemicals in Industry
Principal axis: A straight line which passes through the optical centre of a lens and the focal point. p. 205 Form 5 · Chapter 7: Light and Optics
Proton number: The number of protons in the nucleus of an atom. p. 171 Form 4 · Chapter 8: Elements and Substances
Psychotherapeutic medicine: Modern medicine used to treat psychiatric patients: stimulants, antidepressants and antipsychotics. p. 207 Form 4 · Chapter 10: Chemicals in Medicine and Health
Pulse points: Areas on the body where the pulse can be felt because the arteries are located very close to the surface of the skin. p. 37 Form 4 · Chapter 3: Techniques of Measuring the Parameters of Body Health
Pulse rate: The measurement of the number of heartbeats per minute (bpm). p. 37 Form 4 · Chapter 3: Techniques of Measuring the Parameters of Body Health
Purification of metals: Electrolysis with the impure metal as the anode and the pure metal as the cathode. p. 191 Form 5 · Chapter 6: Electrochemistry

R

Radioisotope: An unstable isotope that emits radioactive radiation. p. 176 Form 4 · Chapter 8: Elements and Substances
Rate of reaction: The change in the quantity of reactant or product per unit time. p. 118 Form 5 · Chapter 4: Rate of Reaction
Recombinant DNA technology: Technology that combines two different species to produce a new genetic characteristic. p. 100 Form 4 · Chapter 5: Genetics
Reusable launch vehicle (RLV): A launch vehicle which can be used again. p. 239 Form 5 · Chapter 9: Space Technology

S

Safety shower: Used to immediately clean and rinse parts of the body or clothing that have come into contact with chemical substances. p. 5 Form 4 · Chapter 1: Safety Measures in the Laboratory
Saponification: The production of soap from the reaction between oil and concentrated alkali. p. 167 Form 5 · Chapter 5: Carbon Compounds
Saprophyte: An organism that obtains nutrients from dead and decaying organisms. p. 7 Form 5 · Chapter 1: Microorganisms
Satellite: An object which orbits planets or stars. p. 236 Form 5 · Chapter 9: Space Technology
Sex chromosomes: Chromosomes carrying genes that determine gender, male or female. p. 78 Form 4 · Chapter 5: Genetics
Sex-linked trait: A trait whose gene is located on the sex chromosomes, such as haemophilia. p. 94 Form 4 · Chapter 5: Genetics
Side effects: Undesirable effects of drug use. p. 211 Form 4 · Chapter 10: Chemicals in Medicine and Health
Silica: A compound that contains silicon dioxide and exists naturally in sand; the material glass is made of. p. 189 Form 4 · Chapter 9: Chemicals in Industry
Simple chemical cell: Two different metals immersed in an electrolyte and connected to an external circuit with connecting wires. p. 192 Form 5 · Chapter 6: Electrochemistry
Socio-scientific issues: Open problems that are controversial social issues related to science; they emphasise moral and scientific applications on real-world situations. p. 56 Form 4 · Chapter 4: Green Technology for Environmental Sustainability
Somatic effects: Effects of radiation on the exposed person, such as tiredness, nausea, cataract, leukaemia and hair loss. p. 265 Form 4 · Chapter 12: Nuclear Energy
Space junk: Non-functioning satellites, used parts of ELV, satellite debris from collisions, exhausted rockets and other waste in space. p. 242 Form 5 · Chapter 9: Space Technology
Speed: The rate of change of distance. p. 228 Form 4 · Chapter 11: Force and Motion
Sphygmomanometer: The instrument used to measure blood pressure. p. 41 Form 4 · Chapter 3: Techniques of Measuring the Parameters of Body Health
Spores: Microscopic cells released by a sporangium that germinate without fertilisation. p. 7 Form 5 · Chapter 1: Microorganisms
Stability: The ability of an object to maintain its original position. p. 126 Form 4 · Chapter 6: Support, Movement and Growth
Standard Operating Procedure: The procedure used for managing biological waste substances in a laboratory (SOP). p. 8 Form 4 · Chapter 1: Safety Measures in the Laboratory
Steel: Alloy of iron 99% and carbon 1%; hard and strong, used for buildings, bridges and railway tracks. p. 184 Form 4 · Chapter 9: Chemicals in Industry
Sterilisation: The process of killing or eliminating microorganisms from an object or a particular surrounding. p. 34 Form 5 · Chapter 1: Microorganisms
Superconductor: A material that conducts electricity at high efficiency without resistance and resists a magnetic field. p. 188 Form 4 · Chapter 9: Chemicals in Industry
Synovial fluid: Fluid that lubricates the joint and provides nutrients to the cartilage. p. 129 Form 4 · Chapter 6: Support, Movement and Growth
Systolic pressure: The top number of a blood pressure reading; the pressure on the wall of blood vessels when the heart muscles contract. p. 41 Form 4 · Chapter 3: Techniques of Measuring the Parameters of Body Health

T

Target organ: An organ that responds to a hormone; it has a suitable receptor for that hormone. p. 145 Form 4 · Chapter 7: Body Coordination
Temperature: A measurement of the degree of hotness and coldness of a substance. p. 34 Form 4 · Chapter 3: Techniques of Measuring the Parameters of Body Health
Tendon: A connective tissue of strong, inelastic fibres that connects muscles to the bone. p. 129 Form 4 · Chapter 6: Support, Movement and Growth
Thyroxine: Thyroid hormone that controls the rate of metabolism and physical and mental development in children. p. 148 Form 4 · Chapter 7: Body Coordination
Ticker timer: A device that vibrates 50 times per second and marks dots on ticker tape. p. 232 Form 4 · Chapter 11: Force and Motion
Traditional medicine: Medical treatment using plants, animals and natural substances to diagnose and treat diseases. p. 204 Form 4 · Chapter 10: Chemicals in Medicine and Health

U

Upcycle: A recycling process that produces new products of higher value than the original product. p. 91 Form 5 · Chapter 3: Sustainability of the Environment

V

Variation: The differences in characteristics among individuals from the same species. p. 103 Form 4 · Chapter 5: Genetics
Velocity: The rate of change of displacement; its sign shows the direction of motion. p. 229 Form 4 · Chapter 11: Force and Motion
Venturi effect: The narrower the part of the Venturi tube, the lower the pressure in the flowing fluid. p. 227 Form 5 · Chapter 8: Force and Pressure
Venturi tube: A non-uniform tube with a narrower centre. p. 227 Form 5 · Chapter 8: Force and Pressure
Vulcanisation: A process of heating rubber with sulphur, giving vulcanised rubber. p. 196 Form 4 · Chapter 9: Chemicals in Industry

W

Withdrawal symptoms: Shivering, nausea, anxiety and depression when an addict stops taking drugs. p. 154 Form 4 · Chapter 7: Body Coordination

Z

Zero gravity: The condition when no significant gravitational force effect is felt. p. 241 Form 5 · Chapter 9: Space Technology