Ito E, Komatsu T, Suzuki H
Division of Biological Sciences, Graduate School of Science, Hokkaido University, Sapporo, Japan.
Biophys Chem. 1998 Aug 4;74(1):59-70. doi: 10.1016/s0301-4622(98)00165-3.
We first showed a general theory that reception of information from the outside in a receptor system is accompanied both by an inflow of entropy and by a generation of entropy depending on the reliability of the actual reception mechanism. Then, considering a case for the absorption of light by the visual-pigment system of visual cell, we calculated the time(t)-dependent change in the number N2(t) of excited visual-pigments to obtain the entropy increase. We thus arrived at the following four conclusions: (1) One or two photons can be detected with a reliability of at least 54%; (2) In compensation for this detection, entropy > 1.12 x log2 is generated; (3) An incident photon of frequency v from a ligh source of temperature Ts yields an entropy of hv/Ts; and (4) Depending on the characteristics of the visual-pigment system, another entropy being different from (2) is generated in proportion to N2(t).
