Biology key terms

A feature that develops at puberty and distinguishes the sexes but is not itself a reproductive organ, such as breast development or a deeper voice.

A new tumour formed in another part of the body after malignant cells have spread from the original tumour.

A collection in which seeds from many plant varieties or species are kept under controlled conditions to conserve genetic material.

The inactive state of a viable seed before conditions allow it to germinate.

A feature carried by a vector that enables cells containing the vector to be identified or selected.

An environmental factor that affects which individuals are more likely to survive and reproduce.

Choosing organisms with desired inherited characteristics to breed, so those characteristics become more common in later generations.

A weedkiller that kills certain plants while leaving others relatively unharmed.

A membrane that allows some substances to pass through but prevents others from passing through freely.

The return of particular useful substances from the kidney tubules to the blood according to the body’s needs.

The ability of a medicine to affect a microorganism more than the host because it targets structures or processes that differ between their cells.

A weedkiller that kills particular types of plant while leaving others relatively unaffected.

The ability of an instrument or method to detect a change in the quantity being measured.

A nerve cell that carries electrical impulses from a sensory receptor towards the central nervous system.

A nerve cell that carries electrical impulses from a receptor towards the central nervous system.

A specialised cell or group of cells that detects a particular type of stimulus.

The muscular wall separating the right and left sides of the heart, preventing their blood from mixing.

The order in which bases or amino acids occur in a molecule.

Waste water containing human waste and other organic material.

One of the chromosomes involved in determining biological sex; in humans these are X and Y.

Inheritance in which a gene responsible for a characteristic is located on a sex chromosome, usually the X chromosome in the GCSE examples studied.

An infection transmitted mainly through sexual contact.

An infection that can pass from one person to another through sexual contact.

Reproduction in which male and female gametes fuse, mixing genetic information and producing varied offspring.

Rapid, involuntary contractions of skeletal muscles that help warm the body.

A focusing defect in which distant objects appear blurred because their light is focused in front of the retina.

A focusing defect in which distant objects appear blurred because light is brought to a focus in front of the retina.