Note on the Effect of Light on the Bioelectric Potentials in the Avena Coleoptile

Abstract

The apex of the etiolated Avena coleoptile is normally electronegative to the base if constancy of measurements is allowed to obtain in complete darkness. On illuminating from all sides with 800,000 mcs, this potential difference suffers a regular variation such that the negativity of the apex at first decreases, then increases to a maximum, and again decreases. This variation is localized mostly in the actively growing sub-apical zone and strongly resembles light-growth reactions.