AQA GCSE Combined Science Trilogy key terms

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.

Follicle-stimulating hormone: a hormone released by the pituitary gland that stimulates egg maturation in the ovaries.

A molecule of carbon atoms arranged in a hollow shape, with a structure based on carbon rings.

An internal biological process that helps an organism survive in its environment.

A chemical that kills fungi or inhibits their growth.

A reproductive cell, such as an egg or sperm, containing one chromosome from each pair rather than both.

An electromagnetic wave originating from a change in an atomic nucleus.

The exchange of oxygen and carbon dioxide between an organism and its surroundings.

The force exerted per unit area by gas particles colliding with the walls of their container.

A section of DNA that carries information affecting an organism’s characteristics and can be passed on to offspring.

All the alleles present in a population.

A medical approach that modifies a patient's genetic material to treat a disorder, for example by introducing a working version of a faulty gene.

A crop plant whose genome has been modified by introducing a gene from another organism.

Modification of an organism's genome by introducing a gene from another organism to give a desired characteristic.

An inherited gene change that increases the likelihood of developing a particular disease.

A version of a region of DNA with a different sequence of bases.

Differences in genetic information between individuals in a population.

The complete genetic material of an organism.

The combination of alleles an organism has; for a particular gene, this can be represented by letters such as TT or Tt.

A classification group containing closely related species; its name forms the first word of an organism’s binomial name.

Energy obtained from hot rocks within the Earth.

An extended network containing very many atoms joined by strong covalent bonds, rather than separate small molecules.

A large, regular, repeating three-dimensional arrangement of oppositely charged ions.

A long-term change in climate patterns across the world, including average temperatures and rainfall.

A reduction in the sunlight reaching the Earth's surface because atmospheric particulates reflect sunlight back into space.

A long-term increase in the Earth's average surface temperature.