- Transport of respiratory gases: at the level of the lungs the blood is enriched with oxygen, and then it is released to the various tissues
-Transport and distribution of nutrients absorbed in the intestine
In addition to respiratory gases and nutrients, the blood also carries waste products, such as carbon dioxide and urea, but also hormones, drugs, etc.
-Elimination of waste products, conveying them to the sites responsible for their disposal (CO2 to the lungs; sodium, urea, bile pigments, catabolized hormones, drugs, etc. to the kidneys)
- It has a defense function: thanks to the presence of white blood cells, antibodies, etc.
- Maintains biological constants, such as temperature (blood heats up when it sprays very hot tissues, see muscles during exercise; similarly it can give heat to colder tissues) and pH (there are real blood in the blood buffer systems, capable of keeping the pH relatively constant).
