Key terms & definitions

Competition between states for power, influence and security.

The process through which people acquire political beliefs and preferences, influenced by agencies such as family, education and peers.

A way of arranging political beliefs along a continuum, commonly from left wing to right wing.

A situation in which competing political forces prevent meaningful progress or agreement.

Protests or other challenges to a government that can create political instability.

Cutting a tree’s branches above the reach of grazing animals, allowing new branches to regrow.

A tax charged on individuals rather than on the value of their property or income.

A substance that causes damage to the environment or harms living organisms when released into air, water or land.

A substance whose presence or increased concentration causes harm to organisms or the environment.

The principle that those responsible for pollution should meet the costs of the damage they cause.

The introduction of harmful substances into the environment, damaging air, water, land or living organisms.

The addition of harmful substances to the environment, causing damage to organisms or ecosystems.

The addition of harmful substances to the environment.

Religious uncleanness associated with contact with death, addressed through purification rather than simply ordinary cleaning.

Harmful contamination or disturbance of the environment, including air and water contamination and excessive noise.

Contamination of the environment with harmful substances.

The release of harmful substances into the environment, causing damage to living organisms or their surroundings.

A polymer whose chain contains amide links; nylon is a polyamide.

A family of synthetic polymers used to make fibres, including nylon.

A marriage arrangement in which a woman has more than one husband at the same time.

An ion made from more than one covalently bonded atom, such as nitrate, $NO_3^-$, or sulfate, $SO_4^{2-}$.

A charged group of atoms that acts as a single ion, such as nitrate, $\mathrm{NO_3^-}$, or sulfate, $\mathrm{SO_4^{2-}}$.

A Greek historian, born around 200 BC, whose Histories explained the rise of Roman power. He wrote after the Second Punic War and researched its events.

Having several centres of activity rather than a single dominant centre.

Growing more than one crop species together in the same area.

Growing several crop species or varieties together rather than a single crop.

Having extra fingers or toes; the inherited form studied here is caused by a dominant allele.

A polymer containing many ester links in its chain.

A strong, durable synthetic fibre with low absorbency and good crease resistance, used in clothing and household textiles.

A thermosetting resin used as the matrix in composites reinforced with glass or carbon fibres.