Human body include the heart, lungs and liver. Many organs reside within cavities within the body. These cavities include the abdomen and pleura. The circulatory system comprises the heart and blood vessels (arteries, veins and capillaries). The heart propels the circulation of the blood, which serves as a "transportation system" to transfer oxygen, fuel, nutrients, waste products, immune cells and signalling molecules (i.e., hormones) from one part of the body to another. The blood consists of fluid that carries cells in the circulation, including some that move from tissue to blood vessels and back, as well as the spleen and bone marrow.
Theology of the Body part of longstanding Church tradition — a tradition that was created in the context of scriptural teachings. The ability of the human body to express "truth" through the sexual union of married couples is acclaimed. The moral wrongness of using artificial means to manipulate such a significant aspect of the created body is explained. Dominion over outside forces, and also self-mastery through discipline, are integral human drives. However, the language expressed by bodies, in this context the language expressed during sexual intercourse, is so damaged by the use of artificial contraception that the conjugal act ""ceases to be an act