The reaction may be improbable, but if it is thermodynamically possible, the cell will find a way to use it. The probability of atoms happening to come together in the complex structure that makes up my body is so tiny that it is practically equal to zero. Another difference between the physical and biological approaches to the study of a reaction lies in the matter of isolation. The physicist is apt to attempt to isolate the reaction he wishes to study. In biology, single reactions are rarely encountered.
Most biological reactions are parts of complex chains.
They cannot be fully understood except as members of the chain, or even as parts of an entire living system - the living biological entity. These processes generate the energy that keeps living systems going. This charge tends to pull the electron back toward A. Electrons could not move against such a strong electrostatic attraction. However, if molecule A is a member of a chain and simultaneously receives an electron from a third molecule, its positive charge will be neutralized. Like many biological researchers, I have often worked for long periods, using all the tricks of chemistry, wave mechanics, and mathematics to understand a certain reaction.