(/) Both solutions are made up of the same basic compounds: water and salt (sodium chloride). But its concentration can vary. The amount of sodium chloride in tears is the same as in plasma, the liquid part of blood. Because…
reader question João Pedro dos Santos, Porto Alegre, RS illustrates Felipe Martini edition Felipe van Deursen They were not discovered, but invented. Notes are a convention, an established code for musicians to read scores. But the western model, the famous…
Because of its curvature. Because they are curved, car mirrors give the driver a greater field of vision than the common mirror. This is because the size of a mirror’s reflection is determined by its curvature. Despite looking flat, car…
It can change color because of pigments contained in some foods and medicines we ingest or as a result of some illness. Under normal conditions, the color of pee varies from a light yellow, almost transparent, to dark yellow. This…
Islam emerged in the 6th century in Arabia, a region of the Middle East that was inhabited at the time by about 5 million people. “They were both sedentary and nomadic groups, organized into tribes and clans. The population was…
We don’t want to scare you, but the answer is kind of disgusting: the ′′ wet dog smell ′′ is the result of a chemical reaction of water with some smelly secretions produced by dogs. “When they get wet, these…
Vale-tudo is a combat sport in which, as the name implies, the beating runs wild. In MMA, any type of fight is accepted, from capoeira to jiu-jitsu, including boxing, karate, kickboxing, muay thai, wrestling and other martial arts. Ultimate Fighting…
(/) 1. The eye dumps a lot of fluid over the course of a night’s sleep. In addition to the secretion of the conjunctival membrane, which protects the eyeball from foreign bodies, there is the tear, whose function is to…
»> At a glance, it is very difficult to distinguish between these two cousins of the elephant, both of which have been extinct for thousands of years. “The main differences between the mammoth and the mastodon are the period in…
The normal temperature of the human body (37ºC) is regulated by a region of the brain called the hypothalamus – it makes us sweat when the body needs to cool down and makes us shiver when we need to preserve…