The circulatory system is very useful. This system transports the food nutrients, and oxygen to the body cells. It also delivers of carbon dioxide and waste products. This helps the respiratory system by transporting nutrients to keep the lungs clean, and healthy.
Answer:
The endocrine system is a chemical messenger system comprising feedback loops of the hormones released by internal glands of an organism directly into the circulatory system, regulating distant target organs. In humans, the major endocrine glands are the thyroid gland and the adrenal glands.
Explanation:
If you want to serve but don't want to be in combat, sadly your gonna have find another job unless you want to do infantry.