Why human body is a wonderful living machine?

Sweat does not smell bad. You probably won't believe this, because you just need to smell it to refute our statement. And then, if sweat is odorless, why does mankind invent all kinds of deodorants and lotions?

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In fact, the sweat itself really does not smell of anything, since it consists mainly of water. But it also contains acids secreted by the apocrine glands in the armpits, chest and groin. Bacteria on the skin decompose these acids and their waste products give off an unpleasant odor.

Another fact is eyes see the world upside down. This was proved by the physicist Rene Descartes back in the 17th century. He projected an image of a cut out bull's eye onto a paper screen, and it was turned upside down - in accordance with all the laws of physics. The fact is that light is refracted when passing through the cornea and lens, so that the projection of the visible object turns out to be rotated.

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Why then don't we see the world upside down? The point is that our brain flips the picture back, making it correspond to reality (and at the same time gluing images from two retinas into one).

In the 1890s, psychologist George Stratton conducted an experiment....He put on special glasses that flip the image, and wore them for eight days. On the fifth day, his brain simply stopped correcting the picture, and Stratton again began to see the world normally. True, his brain had to get used to it again when he took them off.

There are more than four blood groups. If you ask how many blood groups there are in the world, you will probably say: four... Most likely, you were taught this in school. The first (0) - for 44% of the world's population, the second (A) - for 42%, the third (B) - for 10% and the fourth (AB) - for 4%.

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So, this is not entirely true. In fact, there are 29 blood groups in the world. At least that many were counted International Society of Blood Transfusion. The AB0 and Rhesus antigens, by which the four are distinguished, are not the only ones, there are others. And many of them are named after the patients in whom the corresponding antibodies were first detected. Moreover, it is quite possible that new ones will appear in the future.

Another fact that it is impossible to tickle yourself. When someone else tickles you, you can twitch, laugh, or struggle. But try tickling yourself and you won't succeed.

It is assumed that tickling appeared in the process of evolution as a means of protection from insects, spiders and other unpleasant creatures that crawl over people and can harm them. If you are tickled by someone else, it is also perceived as a threat. But if you tickle itself, the body will not give out a reaction, because it will understand that it is doing this to itself.

But if you find it funny or unpleasant because you are tickling yourself, this is not a good sign that can be a sign schizophrenia or damage to the cerebellum.

Women's heart beat faster... Yes it's a fact if you are a woman, know that your heart is beating 70–72 times in men.

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This is because female sex hormones affect myocardial cells , accelerating their contraction. True, there is nothing to be especially proud of here, since because of this feature, women are more often suffer from tachycardia and arrhythmias.