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Above is a diagram of an open circulatory system. An open circulatory system is made up of a heart, vessels, and hemolymph. This diagram shows how the hemolymph, fluid present in most invertebrates that is equivalent to blood, is circulated throughout the body of a grasshopper.
Blood is the final component of the circulatory system. Blood is made up of a liquid called plasma and three particles called red cells, white cells, and platelets. An average adult has about 5 quarts of blood in their body. The circulatory system works together with other body systems. It works with the respiratory system to deliver oxygen. When you take in a breath of air with your lungs, the oxygen passes into your blood stream.