Final answer:
The acrosomal reaction enables sperm to release enzymes that digest the corona radiata, allowing sperm to reach the zona pellucida and ultimately the oocyte for fertilization.
Step-by-step explanation:
The acrosomal reaction is the process by which sperm release digestive enzymes that allow them to penetrate through the corona radiata, a barrier of granulosa cells surrounding the oocyte. This is a critical step for the sperm to reach the oocyte and achieve fertilization.
The enzymes digest the extracellular matrix of the corona radiata, enabling the sperm to approach the zona pellucida, another protective layer surrounding the oocyte. Upon contact with the zona pellucida, sperm bind to receptors, triggering further acrosomal reaction, and release more enzymes to clear a path through the zona pellucida.
Eventually, a single sperm succeeds in making contact with the oocyte's plasma membrane, resulting in fertilization.