Can we make biochemistry an exact science?
  Biochemists know that the law of mass action is not exact and not very useful because we cannot transfer it (with unchanged parameters) from one condition to another. I argue that exact equations require calibrated multiscale analysis to deal with ions. Exact theories in biochemistry must use mathematics of interactions because biological ionic solutions, derived from seawater, are complex (not simple) fluids. The activity of one ion depends on every other ion. Mathematics of conservative interactions is well understood but friction is another matter. Mathematicians now have now an energetic variational calculus dealing with friction. Complex fluids need variational methods because everything interacts with everything else. Mathematics designed to handle interactions is needed to produce exact equations. If interactions are not addressed with variational mathematics, they are bewildering. The mathematics must include the global properties of the electric field. Flow of charge in one place changes the flow everywhere by Kirchoff and Maxwell laws. Charge changes physical nature as it flows through a circuit. It is ions in salt water; it is electrons in a vacuum tube; it is quasi-particles in a semiconductor; and it is nothing much in a vacuum capacitor (i.e., displacement current). Charge is abstract. The physical nature of charge and current is strikingly diverse; yet, the flow of current is exactly the same in every element in a series circuit. The global nature of electric flow prevents the law of mass action from being exact. The law of mass action (with rate constants that are constant) does not know about charge. The law of mass action is about mass conservation. I believe the law of mass action must be modified to be consistent with the Kirchoff current law if biochemistry is to be an exact science. 
Bob Eisenberg
q-bio.BM q-bio.QM