Biomolecular Basis of Life

Life is considered a characteristic of the biological system that preserves, furthers, or reinforces its existence in a given environment. It is defined descriptively by the capacity for metabolism, homeostasis, self-organization, growth, adaptation, information metabolism, and reproduction. All these are achieved by a set of self-organizing and self-sustaining processes, among which energy and information metabolism play a dominant role. The energy metabolism of the human body is based firstly on glucose metabolism, supplemented by lipid metabolism. All energy-dependent life processes are controlled by phosphate and calcium signaling. To maintain the optimal levels of energy metabolism cells, tissues, and the brain communicate mutually, and as a result of this signaling metabolism, emerges self-awareness which allows for conscience social interactions which are the most significant determinants of human life. Consequently, the brain representation of our body and the egocentric representation of the environment are built. The last determinant of life optimization is limited life/death cycle which exhibits the same pattern at cellular and social levels. This narrative review is my first attempt to systemize our knowledge of life phenomena. Due to the magnitude of this challenge, in the current article, I tried to present knowledge about fundamental life processes, i.e. energy and information metabolism, and thus initiate a broader discussion about the life and future of our species.