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===Chemical requirements for life===
===Chemical requirements for life===
Life requires multiple chemical processes to exist simultaneously in a microscopic space. According to leading water & life chemist Felix Franks<ref>Felix Franks. 2010. "2. Water and Life Friend or Foe?". In Harper, Charles (ed.). Water and Life: The Unique Properties of H2O. CRC Press. ISBN 9781439803561 page 13</ref>
Life requires multiple chemical processes to exist simultaneously in a microscopic space. According to leading water & life chemist Felix Franks, life processes must encompass all of the following functions in sequence:<ref>Felix Franks. 2010. "2. Water and Life Friend or Foe?". In Harper, Charles (ed.). Water and Life: The Unique Properties of H2O. CRC Press. ISBN 9781439803561 page 13</ref>
* To control the synthesis of simple, chiral molecules and their reactions to form complex polymers, based mainly, but not exclusively, on carbon, hydrogen, oxygen, nitrogen, and phosphorus
* To control the synthesis of simple, chiral molecules and their reactions to form complex polymers, based mainly, but not exclusively, on carbon, hydrogen, oxygen, nitrogen, and phosphorus
* To program and direct the assembly of such molecules into supramolecular structures, organelles, cells, organs, tissues, and organisms, that is, the achievement of differentiation in the right places and at the right time
* To program and direct the assembly of such molecules into supramolecular structures, organelles, cells, organs, tissues, and organisms, that is, the achievement of differentiation in the right places and at the right time
* To control cascades of chemical reactions (e.g., metabolism), resulting in growth to maturity, steady-state maintenance, defense against predators and chemical deterioration, energy- conversion processes, reproduction, followed by a more-or-less rapid senescence and expiry"
* To control cascades of chemical reactions (e.g., metabolism), resulting in growth to maturity, steady-state maintenance, defense against predators and chemical deterioration, energy- conversion processes, reproduction, followed by a more-or-less rapid senescence and expiry
Other researchers have proposed minimal requirements for genes needed for a living organism. A minimal gene set would include genes for:<ref>Joana Xavier, Kiran Patil, Isabel Rocha. September 2014. "Systems Biology Perspectives on Minimal and Simpler Cells". Microbiology and Molecular Biology Reviews. 78 (3): 487–509. doi:10.1128/MMBR.00050-13</ref>
Other researchers have proposed minimal requirements for genes needed for a living organism. A minimal gene set would include genes for:<ref>Joana Xavier, Kiran Patil, Isabel Rocha. September 2014. "Systems Biology Perspectives on Minimal and Simpler Cells". Microbiology and Molecular Biology Reviews. 78 (3): 487–509. doi:10.1128/MMBR.00050-13</ref>
* cellular division
* cellular division
* transport
* transport
* energetic and intermediary metabolism (glycolysis, proton motive force generation, pentose phosphate pathway, lipid metabolism, and biosynthesis of nucleotides
* energetic and intermediary metabolism (glycolysis, proton motive force generation, pentose phosphate pathway, lipid metabolism, and biosynthesis of nucleotides and cofactors)
and cofactors)
* all 20 amino acids
* all 20 amino acids