Blood since ancient times aroused great interesthumanity, or rather its composition and properties. She was credited with many mystical signs. In ancient times it was considered a source of divine energy and endowed with the ability to make the land more fertile. Even in our time, in church rites of some religions, wine is used that embodies the blood of Christ. What, in fact, are its properties?

The proportion of this component in the adult human bodyis about 6-8 percent of the mass as a whole. In children, this figure is even higher, 8-9 percent. Blood constantly circulates throughout the body and all organs.

There are the main four blood groups. Among them there are those that occur quite often, but one of them is a rare blood group. This sign is unchanged throughout the life path of man. What is this and what is the rarest blood group, we will consider further.

The traditional division of blood into groups withusing the "ABO" system and division using the "rhesus" system. As you know, there are four main groups. The first group - I (0), is considered the most common. Its carriers are about 45 percent of all inhabitants of the planet. The second II (A) also occurs quite often, in 35 percent of the Earth's inhabitants, mostly Europeans. Less common is the third group III (B). Only 13 percent of the world's inhabitants have it. Very rare blood type, last, fourth IV (AB). Its carriers are only 7 percent of the world's population. She is considered the youngest.

There are several hypotheses regarding the occurrence ofthe fourth blood group. One of the versions of its appearance is connected with the epidemics that raged on the planet in the last 500 years. As a result, the evolution of the blood occurred, and as a result, this species appeared.

According to another version, this rare blood type occurred as a result of mixing of two races - black and yellow. Such marriages are rare, and accordingly this species is very rare.

Well, the third version of the appearance of the fourtha version of the change in the nature of people's nutrition. Meat was used for food, which is subjected to a longer heat treatment. Many products of artificial origin have appeared. However, until the end of this issue scientists have not yet been studied.

The blood group influences the body in many waysrights. It is believed that its character also depends on it. In addition, there are special diets that are selected and appointed depending on this factor.

Also, the dependence of the prevalencea certain group from race and nationality. So, among Europeans the second group of blood dominates. Residents of the East in their majority are the owners of the third. Among the representatives of the Negroid race is predominantly the first group. However, for all inhabitants of the Earth a rare group of blood is the fourth.

It is assumed that the predominance ina certain area of ​​the planet of one of the groups was influenced by the diseases that raged there. For example, plague and smallpox mostly affected people with the first group. Thus, there was a natural selection among Europeans.

In Japan, conducted a study and identifieddependence of the nature of people on their blood group. It is also known that marriage between representatives of different genotypes is undesirable. The genotype, which is resistant to a particular race, is destroyed as a result of a mixed marriage. The child gets a new complex of genes, unstable to biological factors, and the number of hereditary diseases increases significantly.

Perhaps you have learned a lot for yourself: For example, what kind of blood group is rare and what is it related to. But the blood and its properties have not been studied yet, and much remains a mystery.

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