AQA GCSE Combined Science Trilogy key terms

A material through which electric charge can flow.

The protection and careful management of species and habitats to maintain biodiversity.

The principle that energy cannot be created or destroyed, although it can be transferred between stores.

The principle that the total mass stays the same: no matter is created or destroyed.

The principle that, in a closed system, total momentum before an event equals total momentum after the event.

A speed that does not change: equal distances are travelled in equal time intervals.

An organism that obtains food by eating other organisms.

A force between objects that are physically touching.

A method in which small samples are repeatedly removed from a reaction mixture to monitor its progress.

A method used to prevent pregnancy.

A factor kept the same so that it does not provide an alternative explanation for the results.

The direction in which positive charge would flow: from the positive terminal to the negative terminal through an external circuit.

A part of a control system that receives and processes information from receptors, such as the brain, spinal cord or pancreas.

A blood vessel that supplies the heart muscle with blood containing oxygen and glucose.

A disease in which layers of fatty material build up inside the coronary arteries, narrowing them and reducing the supply of oxygen to the heart muscle.

A relationship between two variables in which changes in one are associated with changes in the other. It does not, by itself, establish that one causes the other.

The unit of electrical charge. One coulomb passes a point in one second when the current is one ampere.

The number of radiation detections recorded by a detector per unit time. It is not necessarily equal to the source’s activity because not all emitted radiation is detected.

The number of decays recorded each second by a detector, expressed as counts per second.

A strong electrostatic attraction between a shared pair of electrons and the nuclei of the bonded atoms.

The breakdown of large hydrocarbon molecules into smaller, more useful molecules.

A liquid mixture of hydrocarbons formed over millions of years from buried remains of plankton.

A substance in which aluminium oxide is dissolved during aluminium extraction, forming an electrolyte with a lower melting point than pure aluminium oxide.

Obtaining a dissolved solid as crystals from a solution.

The rate of flow of electric charge, measured in amperes (A).

An inherited disorder of cell membranes caused by a recessive allele, resulting in thick, sticky mucus in the airways and digestive system.

The gel-like material inside a cell where many chemical reactions take place.