The corona radiata is a group of follicular cells surrounding the zona pellucida. It is the gelatinous protective outer coat of the ovum. The thin cap surrounding the head of the sperm, called the acrosome, contains the enzyme hyaluronidase, which is capable of dissolving the corona radiata enabling sperm penetration. Research Corona Radiata
The zona pellucida is a transparent, striated membrane surrounding the ovum and containing the cytoplasm, which gives the cell its body. The zona pellucida contains numerous pores through which nutrition is passed to the cell. Once the zona pellucida has been penetrated by a sperm the ovum becomes resistant to any other sperm. The surface layer of the zona pellucida then moves out to engulf the sperm. The cell membranes of the sperm and egg fuse so that they constitute a single cell called a zygote. Research Zona Pellucida
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Matt and Leela Probert
Abbreviations
Research Corona Radiata
