"The Cardiovascular system is like the ocean constantly full of swimmers. The swimmers (blood) move throughout the ocean(body) and the fish(other systems in the body) help keep the ocean functioning properly. A swimmer(blood) takes a break on the shoreline; brushes off seaweed (excess wastes), takes a sip of Gatorade(nutrients and oxygen) and dives back into the ocean. This scenario describes the process of the removal of carbon dioxide and the entrance of oxygen in the body"