Medieval townhouses were built from stone or brick and were several storeys high.
The pancreas and the liver empty digestive juices into the duodenum.
The eye is one of our most important sense organs. When stimulated by light, electric impulses are produced by its receptors.
The Great ocean conveyor is a planet-wide system of ocean currents, which has a great influence on the Earth´s climate.
The International Space Station is a habitable satellite built with the cooperation of 16 countries.
Wealthy citizens in ancient Rome owned large houses with varied layouts of several rooms.
The difference between the temperature of the polar and equatorial zones causes atmospheric circulation which is affected by a number of factors, including the Earth´s rotation.
The geographic coordinate system enables every location on the Earth to be exactly specified.
Due to the Earth´s tilted axis, the angle of the Sun's rays at given latitudes continuously changes during the year.
The orbits of the 8 planets in our Solar System are elliptical.
The Earth is composed of several spherical layers.
The diameter of the Sun is about 109 times that of the Earth. Most of its mass consists of hydrogen.
Life magazine picked Gutenberg's invention of mechanical movable type printing as the most important event of the second millennium.
A symbol of division and oppression, the Wall tore a city and numerous families apart.
The world famous monument in England still poses mysteries for archaeologist.
The average house in Ancient Greece had a rectangular, geometrical floor plan and two storeys.
Christopher Columbus' three-masted carrack, the Santa Maria was the flagship of his first, landmark voyage.
This animation demonstrates the parts of the head, the trunk and the limbs.
The respiratory system is responsible for the intake of oxygen and the release of carbon dioxide.
The American electrical engineer Edison invented the incandescent light bulb in 1879, which changed our everyday life.
Rotating a geometric shape around a line within its geometric plane as an axis results in a solid of revolution.
The church of the 'Holy Wisdom', once the religious centre of the Byzantine and Ottoman Empires, is a UNESCO World Heritage Site.
