Biology key terms

The total area of all the exposed surfaces of an object, measured in squared units such as cm².

A comparison of an object's surface area with its volume, showing how much surface is available for each unit of volume.

A comparison of an object's surface area with its volume, showing how much surface is available for each unit of volume.

Water flowing over the land into streams, rivers, lakes and seas.

Everything outside the reacting system, from which energy can be transferred or to which energy can be transferred.

The likelihood that a person will develop a particular disease; greater susceptibility means that the disease can develop more easily.

A person who is not immune to a pathogen and can therefore become infected.

Fibres that connect the lens to the ciliary muscles and can pull the lens thinner when taut.

Meeting present needs without using resources or damaging the environment in ways that prevent future generations from meeting their needs.

Fishing carried out at a rate that allows fish populations to reproduce and be maintained for the future.

Producing food in a way that can continue over time without exhausting the resources it depends on.

A visible change in a plant caused by a problem, such as leaf spots, wilting or stunted growth.

A junction between neurones where a chemical messenger transmits a signal across a small gap.

A reaction that joins smaller molecules to make a larger molecule.

A consistent measurement error that shifts readings in the same direction, such as a balance that does not read zero before use.

The circulation carrying blood from the left side of the heart around the body and back to the right side.

The molecule or cell feature that a particular antibody is designed to bind to.

A cell that has a compatible receptor for a particular hormone and can therefore respond to it.

A cell or organ that responds to a particular hormone because it has receptors for that hormone.

Treatment directed at a particular molecular feature of cancer cells rather than acting equally on all cells.

Treatment selected because a patient's cells or diseased cells possess a particular biological feature, often identified using genomic testing.

An organ whose cells respond to a particular hormone.

A tissue or organ containing cells that respond to a particular hormone.

One of the ordered groups used in classification, such as kingdom, family or species.

The biological science of identifying, naming and classifying organisms.

A new or improved practical product, process or technique developed using knowledge and skills.

The temperature increase, calculated as final temperature minus initial temperature.