  Biological information processing is generally assumed to be classical.
Measured cellular energy budgets of both prokaryotes and eukaryotes, however,
fall orders of magnitude short of the power required to maintain classical
states of protein conformation and localization at the \AA, fs scales predicted
by single-molecule decoherence calculations and assumed by classical molecular
dynamics models. We suggest that decoherence is limited to the immediate
surroundings of the cell membrane and of intercompartmental boundaries within
the cell, and that bulk cellular biochemistry implements quantum information
processing. Detection of Bell-inequality violations in responses to
perturbation of recently-separated sister cells would provide a sensitive test
of this prediction. If it is correct, modeling both intra- and intercellular
communication requires quantum theory.
