Combined Science key terms

Separation of an insoluble solid from a liquid or solution using a filter.

A resource with a limited supply that is not replaced as quickly as it is used.

The breeding and raising of fish in managed tanks or enclosures, usually to provide food for humans.

A long, tail-like structure that enables a cell, such as a bacterium, to move.

How easily a substance ignites and burns.

Describes a substance that catches fire easily.

A rule relating force, magnetic field and conventional current: the left thumb indicates force, the first finger field and the second finger current, with all three held at right angles.

A substance that can flow, such as a liquid or a gas.

The absorption of radiation followed by the emission of light; for example, a fluorescent coating absorbs ultraviolet and emits visible light.

A structure in an ovary in which an egg matures; the developing follicle produces oestrogen.

A representation of feeding relationships in which arrows show the transfer of material and energy from one organism to another.

A network of linked food chains showing feeding relationships between organisms.

A push or pull acting on an object due to its interaction with another object.

A mixture that has been designed as a useful product.

The simplest whole-number ratio of ions represented by the formula of an ionic compound. For example, NaCl represents one sodium ion for every chloride ion.

The reaction that converts the substances on the left of a chemical equation into the substances on the right.

The preserved remains or traces of an organism from millions of years ago, found in rocks.

A carbon-containing fuel formed over millions of years from the buried remains of organisms, such as coal, crude oil or natural gas.

All the known fossils, which provide evidence about life in the past and how organisms have changed over time.

A mixture separated from crude oil that contains hydrocarbons with similar numbers of carbon atoms and similar boiling points.

Separation of liquids with different boiling points using a fractionating column, in which vaporisation and condensation occur repeatedly.

A diagram showing a chosen object or system on its own, with labelled arrows representing the external forces acting on it.

Motion in which gravity is the only force acting on an object.

The change of state from liquid to solid.

The number of complete cycles each second, measured in hertz (Hz).

Water with low levels of dissolved substances, found in sources such as rivers, lakes and the ground.

A force between surfaces in contact that opposes sliding. Friction between tyres and the road provides grip.