Small intestine is to nutrient absorption as blood is to nutrient distribution. Blood has several functions. One of the major functions is to transport nutrients to every cell in the body. Other functions include: 1. Respiration- delivers oxygen to the cells and removes carbon dioxide from them. 2. Waste removal - disposes of waste products and toxic materials which would otherwise harm the body if allowed to accumulate. 3. Immunity- helps protect the body from disease. 4. Cellular communication- transports hormones from glands to the target cells and organs. 5. Thermoregulation- blood serves to both warm and cool the body as it circulates.