【Chris】評論
As the fertilizing spermatozoon penetrates the ooplasm, at least three types of postfusion reactions occur to prevent other spermatozoa from entering the secondary oocyte (polyspermy). These events include the following:Fast block to polysperm y. A large and long-lasting (up to 1 minute) depolarization of the oolemma creates a transient electrical block to polyspermy.Cortical reaction. Changes in the polarity of the oolemma then trigger release of Ca2+ from the ooplasmic stores. The Ca2+ propagates a cortical reaction wave in which cortical...