Edexcel GCSE Biology key terms

A selectively permeable boundary formed by the brain's capillaries that restricts the movement of many substances from the blood into brain tissue.

The amount of glucose present in a given volume of blood.

The force exerted by circulating blood on the walls of blood vessels.

A type of white blood cell involved in the specific immune response; B-lymphocytes produce antibodies and form memory lymphocytes.

A cell of the body other than a gamete, such as a skin cell.

A measure relating a person's mass in kilograms to the square of their height in metres, used as an indicator of body size and possible health risk.

A layer of relatively still air next to a leaf, in which water vapour can accumulate.

A cup-shaped structure at the start of a nephron that collects liquid filtered from the glomerulus.

The processes carried out by the brain, such as movement, sensation, memory and language.

The chemical splitting of larger molecules into smaller molecules.

A protein made using instructions in certain Bt genes that is toxic when eaten by particular susceptible insect pests.

A method of determining an energy transfer by measuring a temperature change in a known mass of a substance such as water.

A disease in which abnormal cells divide uncontrollably and may invade other tissues.

A very narrow blood vessel with a wall one cell thick, where substances are exchanged between blood and surrounding tissues.

The movement of carbon between the atmosphere, living organisms and other parts of the environment.

The volume of blood pumped out of a ventricle in one minute, usually measured in millilitres or litres per minute.

Disease affecting the heart or blood vessels.

A group of diseases affecting the heart or blood vessels.

An individual who has one recessive disorder allele but does not show the disorder because the other allele is dominant.

A substance that increases the rate of a chemical reaction without being used up by the reaction.

A clouding of the eye’s lens that reduces the light reaching the retina and makes vision blurred.

A relationship in which one factor contributes directly to an effect through a biological mechanism.

The ordered sequence in which a cell grows, copies its DNA and divides.

The process by which an unspecialised cell becomes a specialised cell with structures suited to a particular function.

The production of new cells from an existing parent cell.

An increase in the length of a cell, contributing to growth of a plant organ.

The selectively permeable boundary that controls the movement of substances into and out of a cell.