I am alive because I comply with the numerous properties of life that emerge from complex organization. This can be explained in terms of the hierarchy of biological organization-a pattern explaining the high degree of order evident in my existence. Atoms are identified as the basic building blocks of life. These atoms bond together into molecules and in turn bond together into complex molecules. Life is characterized by the existence of complex molecules. .
Continuing upward in the hierarchy of biological organization, complex molecules cluster together into organelles to form part of a larger structure. These include a nucleus that carries genetic material, mitochondria that generate energy, ribosomes that manufacture proteins, and a thin lipid membrane that surrounds the cell. These numerous organelles in turn cluster together according to their function and form part of the cell. Being a multicellular organism, similar kinds of cells are organized into structural and functional units called tissues, which make up the organism as a whole. .
Ascending the hierarchy, the tissues cluster into organs. It is the compliance of each level of this hierarchy with its emergent properties that constitutes the degree of order in my existence and defines my existence as an organism and a group of the same organisms forms a population. Such is the complete explanation of the hierarchy of biological organization.Compliance to this hierarchy satisfies only one of the seven essential properties of life: order. .
Secondly the organism must satisfy the property of reproduction. If it fail to reproduce its own kind then this very species will cease to exist. Hence, reproduction is essential for life to continue. Life only comes from life. Another property of life is that of growth and development-a property simply stating that the DNA directs the growth and development to ensure that the organism is acharacteristic of my species.