What does blood do?

Transportation is the basic function of blood. Oxygen inhaled from the lungs and nutrients absorbed by the digestive tract are transported by blood to all tissues of the whole body. At the same time, carbon dioxide and other wastes produced by tissue metabolism are also transported to the lungs and kidneys through blood for excretion, thus ensuring the normal metabolism of the body. The transportation function of blood is mainly completed by red blood cells.

Hormone secretion directly enters the blood and reaches the corresponding target organs through blood transport, thus playing a certain physiological role. It can be seen that blood is the contact medium of body fluid regulation. In addition, enzymes, vitamins and other substances also rely on blood transmission to play a role in regulating metabolism.

Because of the continuous circulation of blood and extensive communication with various parts of body fluids, it plays a decisive role in water-electrolyte balance, pH balance and the constant body temperature.

Extended data:

Maintaining the normal excitability of various tissues in the body requires a suitable and constant internal environment, such as temperature, pH, osmotic pressure and various ion concentrations. Blood plays a very important role in maintaining a constant internal environment.

For example, the buffer system in blood (such as sodium bicarbonate and carbonic acid, plasma protein, hemoglobin in red blood cells, etc.). ) has the function of buffering acidic or alkaline substances, and keeps the pH value of blood at 7.35 ~ 7.45. The content and proportion of various inorganic ions in plasma are very important to maintain the normal excitability of nerves and muscles, especially the excitability of myocardium.

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