Chemical reactions upholding biological functions and structures are the process of measurement taking place among the participating chemical reactants. Chemical reactions occurring in thermal environments are either endothermic or exothermic. In particular, exothermic reactions that can live with temperature gradients of exogenous origin could potentially be competent enough to synthesize a robust quantum as a heat engine. Molecular organizations leading to the origin of the phenomenon of life might have been associated with the emergence of a quantum coherence embodied in a robust heat engine feeding on quantum decoherence. Evolutionary maintenance of a robust quantum heat engine, once appeared, can further be empowered by the build-up of temperature gradients of endogenous origin. Biology enriches the repertoire of quantum mechanics so as to include a robust heat engine as a legitimate member of a quantum in addition to the already established member of a quantum including an atom, molecule, and macromolecule.