ELECTROKINETIC STUDIES OF MARINE OVA. VII. RELATION BETWEEN THE ZETA POTENTIAL AND ADHESIVENESS OF THE CELL MEMBRANE OF SEA-URCHIN EGGS

¹ Misaki Marine Biological Station, Misaki, Kanagawa-ken, and Zoology Department, Faculty of Science, Tokyo Imperial University, Tokyo

1. A simple apparatus is described for measuring the adhesiveness of the cell membranes of sea-urchin eggs by the stream method.

2. By constructing a curve of the percentages of remaining cells in different current strengths (remainder curve), adhesiveness is expressed by the area circumscribed by the curve and the two axes.

3. In Anthocidaris eggs, when the zeta potential is changed by hydrogen ions, the adhesiveness changes correlatively and the shifts in the potential and the adhesiveness are both perfectly reversible.

4. In Strongylocentrotus pulcherrimus, both the potential and the adhesiveness change pari pasu when cerium ions are added to the medium. Adhesiveness is maximum at the isoelectric point.

5. Specific effects of individual ions play a secondary role in determining the membrane adhesiveness.

6. Related phenomena are discussed.