AQA GCSE Combined Science Trilogy key terms

A tiny air sac in the lungs where gases are exchanged between air and blood.

A small molecule that can join with other amino acids to form a protein.

A meter that measures electric current and is connected in series with the components being tested.

The unit of electric current. A current of one ampere means one coulomb of charge passes a point each second.

The maximum displacement of a point on a wave from its undisturbed position. Amplitude is measured in metres (m).

A carbohydrase enzyme that breaks down starch into sugars.

The breakdown of organic matter by microorganisms without oxygen.

Respiration that transfers energy from glucose without using oxygen. In muscle cells, it produces lactic acid.

The angle between the incoming ray and the normal.

The angle between the transmitted, refracted ray and the normal.

A salt containing no water of crystallisation.

A negatively charged ion, formed when an atom gains electrons.

The positive electrode during electrolysis, where negatively charged ions lose electrons.

A result that is noticeably different from the other results or the overall pattern.

A medicine used to treat bacterial infections by killing bacteria or stopping their growth; it does not treat viral infections.

The ability of bacteria to survive an antibiotic that would normally kill them.

A protein produced by white blood cells that binds to a specific pathogen and helps the body destroy it.

A molecule on a pathogen’s surface to which a specific antibody can bind.

A medicine used to control HIV infection by reducing the virus's reproduction.

A protein produced by white blood cells that neutralises a toxin produced by a pathogen.

Dissolved in water; shown by the state symbol (aq) in a chemical equation.

A solution in which water is the solvent.

The sum of all values divided by the number of values.

A blood vessel that carries blood away from the heart.

A mechanical device that pumps blood to support or replace the pumping action of a failing heart.

An electrical device used to correct irregularities in heart rate.

Reproduction involving one parent, no fusion of gametes and the production of genetically identical offspring through mitosis.

The layer of gases surrounding the Earth.