Which process explains why sperm penetration triggers oocyte activation during mammalian fertilization?

💡 Explanation

Sperm penetration initiates an increase in intracellular calcium in the oocyte, because this calcium influx triggers the cortical reaction, a process which prevents polyspermy and activates the egg. Therefore, calcium influx is responsible for oocyte activation, rather than capacitation, acrosomal reactions, or mitochondrial transfer.

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