OCR GCSE Biology A key terms

The covalent bond formed between glycerol and a fatty acid in a triglyceride.

A gaseous plant hormone that promotes processes including fruit ripening, flower opening and leaf shedding.

A question concerning whether an action and its consequences are right or wrong.

Questions about whether an investigation and its possible consequences are right or wrong, including consent, privacy, harm and fairness.

A cell whose genetic material is enclosed in a nucleus, such as a plant or animal cell.

The change of liquid water into water vapour.

A change in the inherited characteristics of a population over time, through natural selection, which may result in the formation of new species.

The movement of substances between an organism and its surroundings, across a cell surface or specialised surface.

A specialised boundary across which substances pass between an organism and its environment.

The removal of waste substances made by metabolic processes, such as urea or carbon dioxide.

A reaction that transfers energy to the surroundings.

A molecule with a hydrocarbon chain that can attach to glycerol when a lipid is synthesised.

Anaerobic respiration in microorganisms such as yeast, producing ethanol and carbon dioxide.

A vessel in which microorganisms are grown under controlled conditions.

The joining of two gametes to form a zygote.

A substance added to soil or a growing solution to supply mineral ions needed by plants.

An insoluble protein that forms a mesh across a wound, trapping blood cells to form a clot.

A soluble protein in blood plasma that is converted into fibrin during clotting.

The area of the specimen visible through the microscope at one time.

The fluid formed from filtered blood that passes along a nephron and is modified as substances are reabsorbed.

Reproductive success: how effectively an organism survives and passes its alleles to the next generation in its particular environment.

A transfer of material from one store to another within a cycle.

The point at which light rays meet to produce a sharp image.

A hormone released by the pituitary gland that stimulates an ovarian follicle and its egg to mature.

A sequence showing how biomass and chemical energy are transferred between organisms by feeding.

A situation in which people have reliable access to enough suitable food.

A network of interconnected food chains showing feeding relationships in an ecosystem.