Coordinates muscles controlling breathing ..
Hope it helps.
The cardiovascular system is a system of organs that facilitates the circulation of blood to all parts of the body. Blood is required to reach all living cells as the blood carries essential elements for cell life and regulation, such as nutrients, amino acids, electrolytes,oxygen and hormones. The blood also has a role in maintaining body temperature, fighting diseases, maintaining a stable pH and maintaining homeostasis. The blood also carries carbon dioxide away from the cells. The cardiovascular system consists of a network of arteries, veins and capillaries, as well as the heart, which acts to pump blood around the body, Blood leaves the heart via arteries and return via veins. The lymphatic system transports lymph, typically at a much slower rate than blood. The lymphatic system is an important part of the immune system. Unlike the cardiovascular system, the lymphatic system is not a closed system. The cardiovascular system processes a lot of blood each day through capillary filtration, which separates the blood cells from the plasma. Not all plasma is re-absorbed into the blood vessels, and the lymphatic system is responsible for returning the remaining plasma to the cardiovascular system. <span> </span>
I believe that what is meant with the phrase "older explanation" is none other that superstition. Therefore, I will give you one superstitious belief which is now explained by science.
In Southeast Asia, people used to believe that St. Elmo's fire appears in remote areas because a bloody battle occured in that place leaving disembodied souls of the dead wandering there in the night and even in sunshine!
For generations, many people believed that this is a fact and some even say that these apparitions are diabolical or demonic in nature. So often, caution is advised to people whenever a ball of fire appears out in the open.
However, recent breakthroughs in the 21st century helped scientists to explain this mysterious phenomena. They found out that St. Elmo's fire is actually plasma, nothing special. Now, plasma is considered one of the states of matter! But mind you, it still does not explain why St. Elmo's fire seems to have a mind of its own!
