What is the hymen for?

(Playback/Playback) Biologically, for nothing. It may even be that this film, present at the entrance to the vaginal canal, helps to prevent genital infections in children, but nothing scientifically proven. The hymen appears at the beginning of the development of…

How is the rainbow formed?

(/) Greek mythology would say that he appears whenever the goddess Iris leaves a colored trail in the sky, to convey to men the messages of Zeus, the almighty one of Olympus. The scientific explanation is far less romantic. The…

How does rust form?

»> Just three ingredients: iron, water and air. “Rust is the result of the reaction between iron and oxygen”, says chemist Jorge Masini, from USP. That is: when these two elements come together, they tend to unite to form a…

How is the condom made?

The great secret of the condom production process is vulcanization, that is, a chemical reaction that increases the resistance of the rubber without making it lose its elasticity. As a matter of fact, if vulcanization did not exist, ultra-elastic condoms…