The circulatory system

The circulatory system is an organ system that permit to the blood to go around the body and trasport nutrients, oxygen, carbon dioxide and hormones and other gases to and from cells.

If the circulatory system doesn´t make his work the body can´t fight against diseases or keep a stable internal enviroment like "homeostasis" (temperature regulation and pH).

The circulatory system has two parts:

- The cardiovascular system.

- The lymphatic system.

The cardiovascular system:

- Utility: the cardiovascular system distribute the blood. We need the blood circulatory system    because is connected to the heart, and when throb the blood goes through the veins to the whole    body.

- Parts (Organs): heart, vessels, blood and veins.

- The cardiovascular system also includes the pulmonary circulation because when the blood arrives    to the lungs is oxygenated and then the systemic circulation provide the rest of the body with the  oxygenated blood. The digestive system also works with the circulatory system because it gives the  nutrients that the heart needs to pump.

- The cardiovascular system is closed because the blood never leaves the blood vessels.

The lymphatic system:

- Utility:  One of the works of the lymphatic system is to ride the body of toxins,waste and other  unwanted materials.The principal fuction of lymphatic system is to transport lymph, that it´s a fluid  that contains infection-fighting white blood cells through the body.

- Parts: The lymphatic system is compound of lymphatic vessels and lymph capillares, lymph nodes  and lymphatic tissues and circulating lymph.

Curious facts:

- If we order all of the blood vessels, arteries and capillares we will get a line of 100 thousand        kilometers.

- The blood vessels are very narrow so the red blood cells must form a row and go one at a time.

- The heart can pump out of the body while it has oxygen.
             

Bibliography:

- Wikipedia.

- Live science.

- Kids Health.

- Explora (Vix).