Bipolarity of Egg of Oyster (Gryphaea gigas (Thunberg))

Abstract

1. In the egg of oyster (Gryphaea gigas (Thunberg)), there are two axes showing metabolic gradient, e.g. KP-axis and egg-axis. The former can be easily detected in the unfertilized egg and the latter in the fertilized one.
2. Karyosome changes its position by turning itself around plasmosome and faces to animal pole without fail after the sperm enters into the egg.