Several ingenious instruments have been invented over the centuries to help in navigating the seas.
Human blood consists of blood cells and plasma.
The Wright Flyer was the first successful powered, heavier-than-air aircraft, designed and built by the Wright brothers.
Eukaryotic cells with nuclei measuring only a few micrometres may contain nearly 2 metres of DNA, coiled multiple times.
Carrier of genetic information in cells.
Standing bodies of water can form in depressions on the surface by both endogenic and exogenic forces, as well as by human activity.
Systemic circulation carries oxygenated blood from the heart to the body, while pulmonary circulation carries oxygenated blood from the lungs to the heart.
Icebergs are blocks of frozen freshwater floating in the sea.
As a result of the revolutionary advances in the Neolithic, settling human communities established the first lasting settlements.
In the Tudor Era around 200 buildings were built on the bridge across the River Thames.
The Giza Necropolis is the only one of the Ancient wonders still intact.
This animation shows the characteristics of domestic light sources, from traditional light bulbs to LED lights.
The apparent movement of the Sun is caused by the Earth's rotation around its axis.
One of the directors of the circular, open-air Renaissance theatre in London was William Shakespeare.
In loudspeakers sound waves are generated by electromagnetic induction.
The Buddhist pagoda of the six Harmonies is located in China, by the River Qiantang.
Human bones are joined together by cartilaginous or synovial joints, sutures or they can fuse together.
Cereals are species of grasses cultivated for their edible grains.
Medieval Syrian water wheels were used to convey water to distant areas.
A Zeppelin is a type of rigid-framed airship.