Rotating a geometric shape around a line within its geometric plane as an axis results in a solid of revolution.
Cereals are species of grasses cultivated for their edible grains.
Wind, as an external force, plays an important role in shaping deserts.
Seawater, as an external force, plays an important role in shaping coastlines.
The first supersonic passenger airliner entered service in 1976.
The life cycle of vertebrates starts with the production of the reproductive cells of an individual and ends with the production of the reproductive cells...
Rivers play an important role in shaping the Earth's surface: they cause erosion as well as carrying and depositing sediment.
The 'wise man' originated in Africa and dispersed throughout most of the continents.
Marie Curie, the only person to win the Nobel Prize in two different sciences, is probably the most famous woman in the history of science.
The intriguing history of this historic castle spans nearly a thousand years.
The animation demonstrates the different flower types of angiosperms.
Built in Neo-Byzantine style, this Orthodox cathedral is one of the symbols of the Bulgarian capital city.
Galileo Galilei's scientific achievements contributed greatly to the advancement of physics and astronomy.
The Code of Hammurabi is the emblem of the Mesopotamian civilization; it contains 282 laws carved into a basalt stele.
This physicist-inventor and electrical engineer who mainly dealt with electrotechnics was undoubtedly one of the most brilliant figures of the second...
The Great ocean conveyor is a planet-wide system of ocean currents, which has a great influence on the Earth´s climate.
Carrier of genetic information in cells.
The New Horizons space probe was launched in 2006, with the objective to study Pluto and the Kuiper Belt.
Carved into a granite cliff, the sculptures of the Mount Rushmore National Memorial depict four great United States presidents.
This animation introduces body parts on a male anatomical model.