GTLE Subject Specialism Integrated Science key terms

The mass of a substance packed into a given volume, usually expressed in grams per cubic centimetre. It explains why some objects float on water while denser ones sink, and helps identify unknown materials.

The three common physical forms a substance can take: solid, liquid and gas. Each differs in how tightly particles are packed and how freely they move, and changes of state occur when energy is added or removed.

The amount of matter in an object, measured in kilograms or grams and unchanged by location. It differs from weight, which depends on the strength of gravity acting on that matter.

The process by which particles at the surface of a liquid gain enough energy to escape as a gas below the boiling point. It speeds up with warmth, wind and greater exposed surface area.

A mixture contains two or more substances physically combined but not chemically bonded, so they can be separated by physical means. A solution is a uniform mixture in which a solute dissolves in a solvent.

The smallest structural and functional unit of a living organism, bounded by a membrane and containing genetic material. Some organisms consist of one cell; others, including humans, are built from many specialised cells.

Grouping organisms or materials according to shared observable characteristics to make study and identification easier. Living things are commonly sorted into kingdoms and further ranks using features such as cell type, feeding mode and body plan.

The variety of living things present in a habitat or on Earth as a whole, spanning differences between species and genetic variation within them. Higher diversity generally makes ecosystems more resilient to disturbance.

A diagram showing the many feeding relationships in a community, with arrows tracing the transfer of energy from producers through herbivores to successive predators. It reveals interdependence and the effects of removing a species.

Producers, mainly green plants, make their own food by photosynthesis. Consumers cannot do this and obtain energy by eating other organisms, as herbivores, carnivores or decomposers.

The one-way passage of energy through an ecosystem, entering as sunlight captured by producers and leaving as heat at each feeding level. Only a small fraction passes to the next level, so food chains are short.

The continuous circulation of water between oceans, atmosphere and land through evaporation, condensation, precipitation and runoff. It purifies and redistributes water and drives much of Earth's weather.

The movement of carbon between the atmosphere, living organisms, soils, oceans and fossil fuels. Photosynthesis removes carbon dioxide while respiration, decay and burning release it, so the balance affects global temperature.

The breakdown of dead organisms and waste by bacteria and fungi, releasing nutrients such as nitrates back into the soil for plants to reuse. It is essential for recycling matter in every ecosystem.

A push or pull that can change an object's speed, direction or shape, measured in newtons. Forces act in pairs, and an object's motion changes only when the forces on it are unbalanced.

A contact force opposing relative motion between surfaces that touch, converting kinetic energy mainly into heat. It can be reduced with lubricants or smooth surfaces, or increased for grip and braking.

The attractive force between any two masses, which on Earth pulls objects downward with an acceleration of about ten metres per second squared. It keeps planets in orbit and gives objects their weight.

The movement of energy from one store or object to another, for example by heating, light, sound, electricity or mechanical work. Energy is conserved overall but often becomes spread out as heat.

A closed conducting path through which electric charge flows from a source such as a battery. Current, measured in amperes, depends on voltage and resistance according to a simple relationship.

A conductor, such as copper, allows electric charge and heat to pass through easily because its electrons are free to move. An insulator, such as rubber or plastic, restricts this flow and is used for safety.

A disturbance that transfers energy through a medium or space without transporting matter. Waves are described by wavelength, frequency and amplitude, and include light, sound and water ripples.

Reflection is a wave bouncing off a surface, as light does in a mirror. Refraction is a wave changing direction when it passes between materials of different density, which makes a straw look bent in water.

The process in green plants and algae that uses light energy to combine carbon dioxide and water into glucose, releasing oxygen. Chlorophyll captures the light, and the glucose supplies energy for growth.

The chemical release of energy from glucose inside cells, using oxygen and producing carbon dioxide and water. It powers all life processes and differs from breathing, which simply moves air in and out.

The breakdown of large food molecules into small soluble ones that can be absorbed into the blood. It involves mechanical chewing and chemical action of enzymes along the digestive tract.

A protein that speeds up a specific chemical reaction in living things without being used up. Each enzyme works best at a particular temperature and pH, and is destroyed by excessive heat.

The heart, blood vessels and blood working together to transport oxygen, nutrients, hormones and waste around the body. The heart pumps blood through arteries, veins and capillaries, with gas exchange occurring in the lungs.

The production of new individuals to continue a species. Sexual reproduction involves gametes from two parents and produces varied offspring, while asexual reproduction produces genetically identical offspring from one parent.

A pathogen is a microorganism, such as a bacterium or virus, that causes disease. Immunity is the body's ability to resist a particular pathogen, gained through infection or vaccination by producing antibodies.

Weather is the short-term state of the atmosphere, including temperature, wind, cloud and rainfall. Climate is the average pattern of weather in a region over many years.

Igneous rock forms from cooled magma, sedimentary rock from compacted layers of sediment, and metamorphic rock from existing rock altered by heat and pressure. Each type reveals part of Earth's history.

Weathering breaks rock down in place through physical, chemical or biological action. Erosion then transports the loosened material by water, wind or ice, reshaping landscapes over long periods.

The Sun and all bodies bound to it by gravity, including eight planets, dwarf planets, moons and asteroids. Inner planets are small and rocky, while outer planets are large and mostly gaseous.

A factor in an investigation that can change or be changed. A fair test manipulates one independent variable, measures a dependent variable, and keeps all other variables constant.

A testable, evidence-based prediction about the relationship between variables, stated before data are collected. It is accepted, rejected or refined in light of the results rather than assumed correct.

Reliability means repeated measurements give consistent results, improved by repeats and averaging. Validity means the investigation actually measures what it claims, which requires controlling other variables and using suitable instruments.

Quantities are recorded with standard international units, such as metres, kilograms, seconds and degrees Celsius, plus an instrument reading and appropriate precision. Correct units and significant figures let others interpret and compare data.

Practices that prevent harm in practical work, including goggles, careful handling of glassware and chemicals, correct disposal, and knowing the location of first-aid and fire equipment before starting.

Renewable resources, such as sunlight, wind and timber, are naturally replenished within a human lifetime. Non-renewable resources, such as coal and oil, are finite and release pollutants when burned.

The ability to understand and evaluate science-related information, such as health claims or environmental reports, and to make informed personal and civic decisions based on evidence rather than anecdote.

A firmly held idea that conflicts with accepted science, such as believing plants get food from soil. Teachers diagnose these through questioning and address them with evidence and cognitive conflict.

Ongoing assessment used during teaching to reveal what learners understand and to adjust instruction. It includes questioning, practical observation and quick quizzes, and is low-stakes compared with final examinations.

An approach in which learners investigate questions themselves, planning methods, collecting and analysing data, and explaining findings. The teacher guides and scaffolds rather than simply presenting conclusions.