AQA GCSE Biology key terms

An organism, usually a plant or alga, that produces biomass by making organic molecules through photosynthesis.

A substance formed in a chemical reaction.

The amount of money remaining after the costs of production have been subtracted from the income from sales.

An ovarian hormone that maintains the uterus lining after ovulation and inhibits FSH and LH.

An organism whose cells lack a nucleus; bacteria and archaea are prokaryotes.

A cell whose genetic material is not enclosed within a nucleus; bacterial cells are prokaryotic.

A digestive enzyme that breaks down proteins into amino acids.

A molecule made from amino acids joined in a particular order.

The process in which cells join amino acids in an order specified by genetic instructions to make a protein.

A eukaryotic organism, usually consisting of a single cell; some protists cause disease.

The stage of development when reproductive hormones cause the body to become sexually mature and secondary sex characteristics develop.

A grid used to display all possible combinations of genetic information from two parents’ gametes.

The opening in the centre of the iris through which light enters the eye.

The separation of the required antibody from cells and other substances after it has been produced.

A scaled diagram showing the relative biomass at each trophic level of a food chain.

A square frame used to sample organisms within a known area.

A substance that produces an observable change indicating whether a particular type of chemical is present.

Selection in which each eligible member of a population or defined group has an equal chance of being chosen.

A gradual change in the distribution of a species, often because environmental conditions in different places have changed.

The volume of blood passing a point per unit time.

The amount of change measured per unit of time; here, oxygen bubbles produced per minute can estimate how quickly photosynthesis is occurring.

A measure of how much change occurs in a given time.

The amount of water lost by a plant per unit time, often estimated by measuring its water uptake.

A comparison of two quantities, such as the estimated area of the cytoplasm compared with that of the nucleus.

A substance that is used up in a chemical reaction.

The time between a stimulus occurring and a person responding to it.

The actual physical size of the object being viewed.