Fig. 8

A representative example of a zebrafish egg with fluorescent microspheres loaded into its periphery. A and F are bright-field images taken before and after activation, respectively. A shows no separation between the chorion and the egg plasma membrane, whereas in F, the chorion is clearly raised (see arrowhead). B to D indicate confocal images taken at an optical plane containing the fluorescent microspheres. The fluorescent image in B was taken before the addition of 0.5% fructose in egg-water and then C and D at 2.5 and 5 min later, respectively. E shows the fluorescent images from B, C, and D superimposed on one another. This demonstrates that the egg does not rotate within its expanding chorion during the activation process. Scale bar is 200 μm.