Carbon dioxide from cells is delivered from the circulatory system back to the system so it can exit the body

carbon dioxide leaves the body through their respiratory system (lungs)

image result for how many calories of energy will 20 grams of carbohydrates provide in one gram provides 4 calories

consuming the right balance of protein, carbohydrates and fat can you maintain a healthy weight and optimize your energy levels. protein and carbohydrates both contain 4 calories per gram, while fat provides 9 calories per gram.