What are the functions of blood?

The functions of blood can be split into 3 categories: protection, transportation and regulation. Your blood protects you from harm by forming blood clots at an injury site (to stop blood loss) and by having white blood cells circulating within it. White blood cells can destroy pathogens (microorganisms that can cause disease).The largest functional category is transportation. In the blood, oxygen is taken to your tissues and carbon dioxide is carried away from them. Hormones, heat, nutrients like glucose and some cells are also transported around the body in the blood.The last category is regulation. Regulating the internal conditions of the body is called homeostasis. One way that the body does this by monitoring your breathing via how acidic your blood is (pH). Another example of blood involvement in homeostasis is blood pressure - water is transported to and from tissues from the blood to make sure that it has the right water content.