The body is composed of living, responding atoms and molecules. These have their own consciousnesses alive in matter, their drive to exist and be within the framework of their own nature. They compose the cells, and these combine to form the organs. The organs possess the combined consciousnesses of each of the cells within them, and in their way the organs sense their own identity.
They have a purpose — that function they provide within the organism as a whole. This cooperation of consciousness continues so that you have a body consciousness that is vital, that strives to maintain its own equilibrium and health.