| Zona pellucida | Corona radiata |
| 1. Zona pellucida is inner, thin and transparent layer surrounding the secondary oocyte. | 1. Corona radiata is the outer thick layer surrounding the secondary oocyte |
| 2. Zona pellucida is a non-cellular layer. | 2. Corona radiata is a cellular layer. |
| 3. Zona pellucida is secreted by the ovum itself. | 3. Corona radiata is formed by follicular cells which are glued together by hyaluronic acid. |
| 4. Zona pellucida is retained for more time after fertilization till the ovum gets implanted in the uterus. | 4. Corona radiata is retained till the ovum gets fertilized. |
| 5. Zona pellucida is digested by zona lysine or acrosin at the time of fertilization. | 5. Corona radiata is digested by hyaluronidase enzyme at the time of fertilization. |
