Mysteries of our body: why a person has four blood types

Imagine that the human body – this is car. Heart – this is his engine, legs – wheels, and blood – it's gasoline. The car may be brand new and serviceable, but if the gas tank is empty – she's not going anywhere.  Similarly, blood is the most important fluid in the human body, which performs a vital function – transport of oxygen to every cell of our body. Determination of the blood group – this is perhaps one of the first tests performed on a child. You can probably answer right now what your blood type is, but have you ever wondered why there are only four blood groups for so many people on the planet? Read the answer to this question right now on estet-portal.com.

Human blood types: why there are four of them

Blood – it is a connective tissue, & nbsp; which is approximately 5-6 liters of fluid circulating through the blood vessels of the human body. Blood has two main components: the liquid part, that is, plasma, and the formed elements: erythrocytes, leukocytes and platelets. Approximately 6-8% of the body weight of an adult is made up of blood.

Blood groups were first discovered in 1901 by the Austrian scientist Landsteiner, but he counted only three of them at that time.

However, a small flaw did not prevent the scientist from receiving the Nobel Prize for his discovery. And six years later, the Czech doctor Jansky was the first to single out another, fourth blood group. Why does a person have only four of them?

Blood types:

• A child can inherit their blood type from their parents;
• factors that determine blood type;
• why did scientists count only four blood types.

Child can inherit blood type from parents

Blood type – this is a constant sign that occurs in a person in the prenatal period, is inherited and does not change throughout life, even under the influence of pathogenic factors. The blood type is determined by the set of genes that the child receives with the maternal and paternal chromosomes. A child can inherit three antigens: A, B and O. The chromosome that he receives from his mother or from his father can have only one gene. Thus, the child receives two genes from the parents, on which it depends which of the four blood groups he will have. You can inherit only those blood antigens that are present in & nbsp; parents.

Factors that determine blood type

It would seem that if a blood type is inherited from parents, then the child should have it either the same as that of the mother, or the same as that of the father. But it often happens that all members of a family of four, for example, a person – blood type is different. What is the secret? Each blood type has its own characteristics, which are determined by the presence of agglutinogens and agglutinins. Agglutinogens – These are antigens that take part in the process of gluing blood cells. There are two such antigens: A and B. Agglutinins – These are antibodies located on the surface of red blood cells and performing an agglutination reaction. They also have two – alpha and beta.  Based on this, four blood groups are distinguished:

1. First group: the child inherits the O gene from the mother and father. There are no agglutinogens, but both agglutinins are present;
2. Second group: the child inherits genes A and O. There is only agglutinogen A and agglutinin beta;
3. The third group: the child inherits genes B and O. There is only agglutinogen B and agglutinin alpha;
4. Fourth group: the child inherits genes A and B. There are agglutinogens A and B, but no agglutinins.

Why did scientists count only four blood types

Today, there are several basic methods for determining blood groups that are performed in medical laboratories using special chemicals. Why did the great scientist Landsteiner fail to see the fourth blood group – remains a mystery. But one thing can be said for sure: in 1901, an Austrian doctor was sure that there were only three blood groups.

The answer to the question "Why are there only four blood types?" simple enough: because to date, science has been able to prove the existence of only four blood types.

From time to time there are suggestions that there are many more blood types. And who knows what amazing mysteries of nature scientists will have to unravel in the future.