THE BIOELECTRIC POTENTIAL OF SEEDS AS A FUNCTION OF GROWTH AND OF X-RAY DOSAGE

When a cell is subjected to x-radiation, small islands of chemical change are produced in the region where energy quanta are absorbed. Because radiation penetrates more or less uniformly all parts of small living systems, these islands are produced probably in all the cell parts (membranes, cytoplasm, nuclei and chromosomes). Thus in an organic system that is complex to start with, many different kinds of molecules are destroyed and likewise many new ones come into existence in a chaotic fashion. These changes produce disorganization in either functional or control activities of the cells, or in both. Experimental observations (4) show that generally functional activity is not easily affected by radiation because of the continuous supply of new material through nutrition. Such processes as respiration, metabolism, and enzymatic activity were found to be little influenced by radiation. Dale (4) has shown that only very large doses reduce the activity of enzymes. This reduction can have little importance in tissue unless the sources of enzymes are inactivated. The exact origin of bioelectric potentials is still open to question although a great deal of work has been done to determine the cause and the seat of the electrical asymmetry responsible for the e.m.f. (5, 6). However, it is recognized that in all biological systems there are a great number of phase boundaries with resulting differences of potential. There undoubtedly are many membrane potentials created by a difference of concentration of the electrolyte on the two sides of each membrane. The islands of ionization produced by the passage of x-rays through biological materials together with the chemical changes caused thereby are bound to affect the bioelectric potentials under any plausible theory of the origin of these potentials. The object of these experiments is to measure the bioelectric potentials of seeds as a function of growth and of x-ray dosage.