This report concerns changes in the cytoplasmic concentration of Na+, Cl-, K+ and Mg2+ during the first cell cycle and into the second cell cycle of fertilized sea urchin eggs of Lytechinus variegatus. The results of electron probe x-ray microanalysis showed a significant equimolar decrease in Na+ and Cl- at the first cell division which was followed by a significant increase early in the second cell cycle. Neither K+ nor Mg2+ showed such significant changes. The loss of a large fraction of the Na+ ions from the egg at metaphase was not accompanied by a significant egg volume change. The observed pattern of ionic change was related to several previously reported chemical and metabolic changes at cell division in sea urchin eggs.
ASJC Scopus subject areas
- Cell Biology