Answer: CAPILLARIES
Explanation: Gas exchange is the delivery of oxygen from the lungs to the blood stream, and the elimination of carbon dioxide from the blood stream to the lungs. It occurs in the lungs between the alveoli and a network of tiny blood vessel is called capillaries, which are located in the walls of the alveoli.
Nitrogen isn't found in carbohydrates or lipids
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She may have Gastritis.
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