Edexcel GCSE Combined Science key terms

The combination of different energy resources used by a country or by the world.

A source from which energy can be obtained for uses such as heating, transport or electricity generation.

A way in which energy is held by an object or a system, such as a kinetic, chemical or thermal store.

A process by which energy moves between stores, such as mechanical working, electrical working, heating or radiation.

Additional warming caused by increased concentrations of greenhouse gases in the atmosphere.

A gradual change in an environmental factor across an area, such as increasing light intensity from shade to open ground.

Differences in characteristics caused by the environments organisms experience.

A biological catalyst produced by a living organism.

The ability of an enzyme to act on particular substrates because their shapes are complementary to its active site.

The temporary combination formed when a substrate binds to an enzyme's active site.

The condition in which forces balance and the resultant force is zero, so there is no acceleration.

An approximate value used when an exact measurement or count is impractical, or to check whether a result is reasonable.

A question about whether an action and its consequences are right or wrong.

An organism whose cells contain a nucleus.

A cell with its DNA enclosed in a nucleus; animal and plant cells are eukaryotic.

Nutrient enrichment of water that causes excessive growth of algae and plants and can lead to oxygen depletion and loss of aquatic organisms.

The change from liquid to gas at the liquid's surface, which can occur below its boiling point.

A change in the inherited characteristics of a population over generations.

A reactant supplied in a greater amount than is needed to react completely with the other reactant, so some remains unreacted.

A surface across which substances move between an organism and its environment, or between different regions within an organism.

A change or reaction in which heat energy is given out to the surroundings.

A reaction that transfers energy to the surroundings.

The increase in an object's length: $x = \text{loaded length} - \text{original length}$.

A diagram tracing the inheritance of a characteristic through generations of a family.

A raw material used to make other substances in industrial chemical processes.

The conversion of sugars into ethanol and carbon dioxide by enzymes in yeast under conditions without oxygen.

The fusion of the nuclei of a sperm cell and an egg cell.