Biology key terms

A single, large, circular DNA molecule found free in the cytoplasm of a bacterial cell.

The copying of DNA to produce two copies of each chromosome before a cell divides.

The order of the bases A, C, G and T along a length of DNA.

Determining the order of nucleotide bases in a section of DNA.

One of the two long chains of nucleotides in a DNA molecule.

A classification group above kingdom in the three-domain system.

An animal whose breeding and way of life have been managed by humans for purposes such as food, work or companionship.

Describes an allele that is expressed in the phenotype when at least one copy is present.

An allele that is expressed in the phenotype when one or two copies are present.

A person who provides cells, tissue or an organ for transplantation.

A period when a viable seed does not germinate, even though it may later be able to grow.

The quantity of a drug given at one time or at stated intervals.

A trial in which neither the patients nor the doctors assessing them know who receives the drug and who receives the placebo until the results are collected.

A system in which blood passes through the heart twice during one complete journey around the body: once on its way to the lungs and once on its way to the rest of the body.

The coiled shape formed by DNA's two strands.

A biological molecule or process in a pathogen or host cell that a medicine is designed to affect.

Mass measured after water has been removed, allowing fairer biomass comparisons between organisms.

A severe viral disease that can spread through contact with the body fluids of an infected person.

A community of living organisms interacting with the non-living parts of their environment.

The benefits that natural ecosystems provide for human wellbeing and quality of life, such as pollination and the supply of useful materials.

Tourism based on experiencing the natural environment that can support conservation and local communities when it is managed sustainably.

The extent to which a medicine produces its intended beneficial effect.

A muscle or gland that produces a response when it receives a signal.

How well a drug produces its intended medical effect.

The removal of undigested and unabsorbed food from the digestive system as faeces.

The ability of a material to return to its original shape after being stretched.

The application of a weak electrical current to a brain area to investigate the response produced.