How do the digestive, circulatory, and respiratory systems work together?

***Digestive system...From the moment you see, smell or even think about a tasty food item, your body prepares itself for digestion, your mouth watering. Secretly, your stomach starts secreting digestive fluids. take a healthy bite and your body’s digestive system swings into full gear.From the mouth, your meal must now journey to its next stop—the stomach
***Circulatory system: The main purpose is to carry oxygen from our lungs to the cells of our body. The circulatory system of the body can be likened to a city’s system of roads, railroads and shipping facilities that supply the daily needs for food and necessary materials of life. It can be described as a system of sewage, sanitation and waste disposal, by blood circulation that provides the distribution of supplies and removal of wastes.
***Respiratory System.... A very special transportation system, the red blood cells, white blood cells and platelets carried around in a fluid called plasma
The main purpose is to carry oxygen from your lungs to the cells of your body
About 85 percent of the iron in the hemoglobin is kept in your body to use in the making of hemoglobin for the new red cells. You do that by eating liver, oatmeal, eggs, spinach—a diet that includes iron-containing foods.
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