Fertilisation And Implantation

The corona radiata and zona pellucida are both layers of the egg (ovum) but serve different functions: - The corona radiata is a layer of follicular cells that surround the egg, providing protection and nutrients. - The zona pellucida is a glycoprotein layer that surrounds the egg, playing a critical role in fertilization by binding sperm and preventing polyspermy. Thus, they are both layers of the ovum but have distinct roles in the reproductive process.