Figure 1.

Schemes showing the methods by which cortical flow was redirected and ectopic furrows were induced. (A) Method used to redirect cortical flow. The oocyte (shown on its side) is positioned in a bed of PMA-containing agarose such that approximately half of the oocyte surface is in contact with PMA. (B) Method used to induce ectopic furrows. The oocyte is positioned and held against PMA-containing agarose with the slope of agarose lacking PMA such that only a very localized area on the oocyte surface is in contact with PMA.