Water permeability in the developing embryo of the zebrafish, Brachydanio rerio

Abstract

The water permeability of developing embryos of the zebrafish, Brachydanio rerio, is measured indirectly by noting the time taken for the embryos to fall through deuterated water. Stages between early high blastula and one-half epiboly were judged to be most permeable to water; we suggest that the change in the ratio of surface area to volume that accompanies decreasing cell size may increase overall permeability.