OCR GCSE Combined Science B key terms

A magnetic material that becomes magnetised in an external magnetic field and usually loses most or all of this magnetism when the field is removed.

A rigid spherical object that does not spring back elastically after deformation, used as a simplified representation of a particle.

An electrode that conducts electricity and provides a surface for electrode reactions without taking part chemically in those reactions.

The tendency of an object to remain at rest or continue moving with constant velocity.

A measure of how difficult it is to change an object’s velocity, defined as the ratio of resultant force to acceleration: $m = F/a$. It is measured in kilograms.

The entry and multiplication of a pathogen in a host organism.

A conclusion reached by reasoning from observations or data, rather than something directly observed.

Difficulty conceiving a child naturally after a long period of trying.

Voluntary agreement to take part in a study after understanding what it involves and its potential risks.

Electromagnetic radiation emitted by Earth’s warm surface and absorbed by greenhouse gases.

A clear region around a disc on a bacterial culture where bacterial growth has been prevented.

The speed of an object at the beginning of the interval being considered, represented by $u$.

Unable to dissolve in a particular solvent.

The rate at a particular moment, found from the gradient of a tangent to an amount–time curve.

A hormone released by the pancreas that lowers blood glucose concentration by stimulating glucose uptake by cells and its storage as glycogen.

A reduced response of body cells to insulin.

The power carried by radiation per unit area, measured in watts per square metre ($\mathrm{W/m^2}$).

Two forces arising from the same interaction: each object exerts a force on the other. They are equal in magnitude and opposite in direction.

The reliance of organisms on other organisms for resources or processes needed for survival and reproduction.

The boundary where two different materials meet.

An attraction between molecules, rather than a covalent bond joining atoms within a molecule.

The total kinetic and potential energy of the particles within a system.

The stage before division during which a cell grows and copies its DNA.

Estimating a value between known data points using the trend shown by the data.

An operation that reverses another operation, such as division reversing multiplication.

The relationship in which light intensity is inversely proportional to the square of distance from a light source: $I \propto 1/d^2$.

An atom or group of atoms with an electrical charge because it has lost or gained electrons.