Why is the blood of a man red, not gray or blue?

Human blood is red due to hemoglobin It, in turn, consists of two particles:

1. Hemo - this element is only 4% of the total percentage. These are elements of ferrous iron.
2. Globin accounts for the remaining 96%. It's protein.

The hemoglobin engine is iron. It is this element that promotes the reproduction of red bodies in the human body.** Blood is necessary for a person, because it circulates through the body, carries human **organs oxygen and useful substances. Therefore, the blood is divided into two types:

1. The arterial is one that moves along the route from the heart to the organs and has a bright red color.
2. Its task is to bring oxygen to everyone. That's why she has such a bright, scarlet color.
   Venous - this is the blood that has fulfilled its task of delivering oxygen and comes back.
   
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   On this route, blood constantly travels through the body. It is an important connecting component for man. The function of blood is not only as a courier. Its components perform the following important functions:

Plasma. It consists of water and useful components. It's like a base for other cells.

Leukocytes. They are real protectors for the body. The task of these cells is to identify the enemies and destroy them.

Platelets. It is for them to determine the ability of the blood to clot. This is necessary in order that, in case of mechanical damage, platelets close the wound and save the person from complete loss of blood.

Еrythrocytes in the blood Erythrocytes. They are in our blood most of all - about 90%. Actually, it is thanks to them that our blood is red. Their task is to deliver oxygen to all cells of our body. At an early stage of its development, red blood cells are gray or blue.

Blood is a very complex organ, which has not been fully studied before. But one thing is certain - plays one of the main roles in our life.