Foreshadowing Emergent Levels of Metabolism

Units of metabolic function are highly variable. 'Units' can range from a single enzyme molecule, to cellular organelles to cells to organs. Interconnections within and between these levels of metabolic function appear seamless. Units of function increase in size from molecules, through tissues, cells, organs and organ systems to a bee or to a population of bees in a colony producing heat warming itself in winter. Each level has its own terminology for description including units of measure. As the size of an individual functional unit increases, at each level and between levels, new emergent functions arise. Topologically, the visible anatomy of a bee shares many distinct boundaries. Examples include cell membranes and the layers of epithelial cells that line the surfaces of organs, but most boundaries between functions remain indistinct. Unlike networks of electronic components in which charge flows through wires, most topological lines between biological functions are indistinct. Some direct mapping between function and form occurs most readily at macro-sized or organ or organ system levels, (heart as a pump) and at macromolecular levels (DNA to RNA to protein), but most intermediate mappings must still be worked out. Lacking detailed nesting maps, we can build at best very imperfect models.

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