Many people have already tried to do this calculation, but there is still no definitive answer. Since the pioneer Anton von Leeuwenhoek predicted in 1679 that our planet could support 13.4 billion people, estimates have varied between 1 billion and…
The difference between these three vision-impairing problems lies in the place in the eye where light rays converge to form the image. “In a normal person, light rays pass through the cornea, which is the first lens of our eye,…
It is basically formed by a mixture of clay and limestone (calcium carbonate rock), which manufacturers call “flour”. “This mixture is taken to the oven at a temperature of 1450ºC, where it remains until the two elements merge”, says chemist…
It is Prague Castle, which, as the name says, is located in the capital of the Czech Republic. The original construction was inaugurated around the year 880 by Prince Borijov (842-894), Count of Bohemia, and – as is often the…
(CheshireCat/iStock) Scientifically known as nevi, they are small benign tumors formed by melanocytes, cells that produce melanin, the pigment responsible for skin and hair color. A concentration of melanocytes greater than normal ends up forming dark spots. When they occur…
They are a nomadic people who live in the deserts of the Middle East and North Africa. Bedouins make up about 10% of the inhabitants of the Middle East and are named after Arabic words. al bedu (“inhabitants of the…
»> These are measurements of the force with which blood passes through the arteries at two moments: when the heart pumps and when it relaxes. Whoever has an index of 12 by 8 has a systolic pressure (at the time…
»> They are basically protective shells of marine molluscs, soft-bodied animals. When they are born, a temporary shell forms around them, called protoconch. When the mollusk grows and reaches young age, the definitive shell begins to form, replacing the first…
»> The first representation of a wheel ever found by archaeologists dates back to 3500 BC – that is, 5,500 years ago – and was made on a clay tablet found in the ruins of the city-state of Ur, where…
»> READ MORE – What were the most important manga in history? – How is the routine of a manga author? The term manga appeared in 1814, in the hokusai manga, which bring caricatures and illustrations about Japanese culture. Modern…