AQA GCSE Combined Science Trilogy key terms

The regulation of the internal conditions of a cell or organism to maintain optimum conditions for function in response to internal and external changes.

A family of compounds with the same general formula and similar chemical properties. Successive members differ by $CH_2$ and show gradual changes in physical properties.

Having two identical alleles of a particular gene.

The relationship $F = ke$: force and extension are directly proportional, provided the limit of proportionality is not exceeded.

A chemical messenger released by a gland and carried in the blood to affect target organs or cells.

An organism in or on which a pathogen lives, obtaining the conditions and nutrients it needs.

A measure of how much water vapour is present in the air.

A salt containing water of crystallisation within its crystal structure.

A compound containing only carbon and hydrogen atoms.

A testable proposed explanation that leads to a prediction.

The body's defence system that responds to pathogens, including the actions of white blood cells.

The attachment and embedding of an embryo in the lining of the uterus.

An additional substance mixed into a sample, making that sample chemically impure.

Breeding between closely related individuals, which can increase the risk of inherited defects in offspring.

The occurrence of new cases of a disease in a population over a specified period.

Burning with an insufficient oxygen supply, which can produce carbon monoxide, solid carbon and unburned fuel.

The factor deliberately changed or compared in an investigation.

A magnetic material that becomes a magnet when placed in a magnetic field and loses most or all of its magnetism quickly when removed.

A permanent change in shape: the object does not return to its original shape when the deforming forces are removed.

A conductor through which current enters or leaves an electrolyte, without reacting with the electrolyte or products under the conditions used.

(HT only) The tendency of an object to remain at rest or continue moving with uniform velocity.

(HT only) A measure of how difficult it is to change an object's velocity, defined as the ratio of resultant force to acceleration: $m = F/a$. Its unit is the kilogram (kg).

Difficulty conceiving a baby.

An instrument that responds to infrared radiation, allowing radiation from different surfaces to be compared.

Electromagnetic radiation that transfers energy and is emitted by warm objects; it is invisible to the human eye.

A condition caused by particular alleles passed from parents to their offspring.

Unable to dissolve in water.