AQA GCSE Combined Science Trilogy key terms

Luteinising hormone: a hormone released by the pituitary gland that triggers ovulation.

An assessment of environmental impacts across all stages of a product’s life, from obtaining raw materials to disposal.

An assessment of a product’s environmental impact throughout its life, from extracting raw materials to disposal, including transport and distribution at each stage.

The amount of light reaching a given area per unit time.

A microscope that uses light and lenses to produce a magnified image of a specimen.

A sedimentary rock made mainly of calcium carbonate, often formed from the accumulated shells and skeletons of marine organisms.

A solution of calcium hydroxide in water, used to test for carbon dioxide gas.

A resource with a finite supply that is not replenished as quickly as it is used.

A condition that restricts the rate of a process; improving that condition increases the rate until another condition becomes limiting.

A reactant that is completely used up in a reaction and therefore limits the maximum amount of product that can form.

The point beyond which extension is no longer directly proportional to the applied force.

A component whose current–potential difference graph is a straight line through the origin, showing constant resistance under the conditions tested.

A relationship represented by a straight line on a graph. A directly proportional relationship has a straight line passing through the origin.

The straight line along which a force acts.

A system developed by Carl Linnaeus that groups organisms into kingdom, phylum, class, order, family, genus and species.

An enzyme that breaks down lipids into glycerol and fatty acids.

Paper containing a coloured indicator that changes colour in acidic or alkaline conditions.

The brown-insulated wire that carries the alternating potential difference from the mains supply; its potential difference relative to earth is about 230 V.

A simplified explanation of enzyme action in which a substrate fits an enzyme's complementary active site, like a key fitting a lock.

A pair of outer-shell electrons that is not shared in a covalent bond.

A wave whose oscillations are parallel to the direction of energy transfer.

An ore containing a relatively low percentage of the metal or metal compound of interest.

A substance used to reduce friction between moving surfaces.

Applying a lubricant, such as oil, between moving surfaces to reduce friction and unwanted heating.

The internal space of a blood vessel through which blood flows.

A type of white blood cell that produces antibodies; some also produce antitoxins.

A region where a magnet or magnetic material experiences a force.

The direction of the force that would act on a north magnetic pole placed at a particular point.