Respiratory system plays a major role of transporting oxygen to the circulatory system which in turn transports it to all cells of the body. Oxygen is very vital substance that helps cells get energy for cellular activities. Apart from supply of oxygen to the body, the respiratory system plays a big role of removing carbon dioxide from the body thus preventing build up of this gas to lethal stage in the body tissues. The main organs associated with respiration are the mouth, nose, pharynx, larynx, trachea, bronchioles lungs and the diaphragm. Lungs aid in removal of carbon dioxide and delivery of oxygen to the circulatory system Though the basic task of respiratory system is the intake and removal of oxygen and carbon dioxide respectively, it also helps in regulating the balance of base and acids in the body, protects body against organisms that cause diseases as well as toxic substances that are inhaled. It is also good to note respiratory system assists in production of speech and sound and houses cells for smell (respiration, 2009).

The circulatory system also called cardiovascular system is tasked with the transport of hormones, metabolic waste, food and gases from and to the cells. Circulatory system is comprised of blood (which consists liquid plasma and cells), heart ( which is a muscular organ that pumps the blood) and blood vessels ( which is made up of  arteries, veins and blood capillaries) arteries are responsible of carrying blood away from the heart, whereas capillaries return blood to the heart. The blood is transported in two circulatory circuits. There is pulmonary circulation which delivers blood to and from the lungs; leading to the oxygenation and removal of carbon dioxide. On the other hand, systematic circulation is involved in carrying of blood to the rest of the body. Through circulation, waste products get removed from the kidney and the liver. Another important component of circulation is the lymphatic system which is a key component that aid body prevent bacteria invasion and helps in elimination of cellular breakdown (circulation, 2009).

In a summary, circulatory and respiration work hand in hand and plays a big deal in maintaining life of the cells of the body.