Beyond the answers - interesting background to this quiz

The bone built for load, not length alone

The femur, or thigh bone, is the longest bone in the human body, but its real claim to fame is strength. It has to carry several times your body weight with every step, jump and landing, which is why it is also one of the toughest bones you have. When it does break, usually only under serious force, it is treated as a major injury rather than a routine fracture.

A mountain range measured in kilometres, not height

The Andes form the longest continental mountain range on Earth, stretching along the western edge of South America through seven countries. Unlike the Himalayas, which are defined by towering individual peaks, the Andes are remarkable for sheer continuity. They also sit above a subduction zone, where an oceanic plate slides beneath the continent, fuelling both the mountains and the region's volcanoes.

The river that crosses more borders than almost any other

The Danube flows through ten countries, more than any other river in the world, passing through Romania on its long journey from Germany to the Black Sea. It has served as a trade route, a Roman frontier and a modern political boundary. Four national capitals sit on its banks, which is part of why it has been so central to Central and Eastern European history.

Fiji's islands: many dots, few homes

Fiji is made up of more than 330 islands, but only about 110 are inhabited. The rest are either too small, too remote or too lacking in fresh water to support permanent settlement. That gap between total islands and lived-in ones shapes everything from ferry schedules to how the country is governed across its scattered territory.

Flerovium and the naming of heavy elements

Flerovium carries the symbol Fl, which is easy to confuse with F for fluorine and Fe for iron. It is a synthetic superheavy element, meaning it does not occur naturally and exists only briefly in laboratories. It is named after the Russian physicist Georgy Flerov, a reminder that element names often honour the scientists and institutions behind their discovery rather than any property of the substance itself.