The document summarizes the respiratory and circulatory systems. It describes: 1) The respiratory system brings oxygen into the body and removes carbon dioxide through a series of organs including the lungs which facilitate gas exchange with blood. 2) The circulatory system transports nutrients, water, oxygen and removes wastes throughout the body via blood flow through components like the heart and blood vessels. 3) Both systems adapt through processes like increased lung alveoli and heart rate to more efficiently oxygenate tissues and remove carbon dioxide as physical activity increases.