Intestines -Its main purpose is to digest food. But the intestine is not only there for digestion: it also produces various substances that carry messages to other parts of the body, and plays an important role in fighting germs and regulating the body's water balance.
Pancreas-During digestion, your pancreas makes pancreatic juices called enzymes. These enzymes break down sugars, fats, and starches. Your pancreas also helps your digestive system by making hormones. These are chemical messengers that travel through your blood.
Heart-The heart is a muscular organ in most animals, which pumps blood through the blood vessels of the circulatory system. The pumped blood carries oxygen and nutrients to the body, while carrying metabolic waste such as carbon dioxide to the lungs.
If you get a career in any medical field then it's important to know about the functions of the body systems. Knowing about how they work will prepare you for what you need to know when you get that job. Learning these things in school helps prevent you from struggling with your career.
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