I am a drop of blood. I am tired and deoxygenated I work very hard. I came from the brain.  I went into the superior vena cava with my friends. So the vein took me. And my friends. Knock knock, Atrium can I come in? “Of course” Replied the right atrium so my friends and I went in. The atrium is the upper chamber of the heart. The tri-cuspid valve opened in one way. There are two valves in the heart. We went into the lower chamber of the heart and I also saw the septum. The septum divides the heart into two sides. Then we went into the pulmonary vein and it took us to the lungs. The lungs are organs in the body when we inhale the lungs get inflated and when we exhale the lungs are deflated.  The heart washed us like if it was a washing machine. From the lungs we went back to the left atrium through the pulmonary vein (the only vein that carries oxygenated blood.) The mitral valve opened and down to the left ventricle the aorta took us back to all the upper organs, and all the cells that were waiting for us patiently. My liquid is plasma and my job is to carry nutrients, waste, and oxygen. If the human body dies unfortunately, will stop functioning  too. It’s too sad.