Combined Science key terms

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.

Medical treatment used to help people conceive, including IVF.

The build-up of fatty plaques in artery walls, which narrows the space through which blood flows.

The mixture of gases surrounding a planet.

A tiny building block of matter, consisting of a central nucleus surrounded by electrons.

A representation of the structure of an atom, developed to explain experimental evidence.

The number of protons in the nucleus of an atom of an element.

A historical name for relative atomic mass: the weighted mean mass of an element’s atoms compared with one-twelfth of the mass of a carbon-12 atom. It accounts for the masses and abundances of its isotopes.

An upper chamber of the heart that receives blood.

The total change in velocity divided by the time taken: $a = \frac{\Delta v}{t}$.

The total kinetic energy of a group of molecules divided by the number of molecules.

The total distance travelled divided by the total time taken for a journey.

The number of specified particles per mole: $6.02 \times 10^{23}\ \text{mol}^{-1}$.

The long extension of a neurone that carries electrical impulses away from its cell body.

Ionising radiation present around us in the environment, even when no deliberate radioactive source is nearby.

A biological extraction method in which bacteria help produce a solution containing metal ions from an ore; also called bioleaching.

A symbol equation with the same number of atoms of each element on both sides of the reaction arrow.

Forces whose combined effect gives a resultant force of zero.

A chemical equation with the same number of each type of atom on both sides.

A number written before a chemical formula in a balanced equation that multiplies the whole formula.

A contraceptive method that creates a physical barrier; condoms also reduce the transfer of pathogens during sexual contact.

A contraceptive method that physically prevents sperm reaching an egg, such as a condom or diaphragm.

The rate at which chemical reactions occur in the body when it is at rest.

A substance that neutralises an acid. Examples include metal oxides, metal hydroxides and metal carbonates.