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the pattern of various chemical changes that occur in the anterior of the head of the spermatozoon in response to contact with the ovum and that lead to the sperm's penetration and fertilization of the ovum.
Acrosomal ReactionA necessary and irreversible step in fertilisation, which is triggered by a sperm receptor, in which the sperm’s and ovum’s plasma membranes fuse and the sperm penetrates the ovum’s zona pellucida.
acrosomal reactionReproductive medicine A necessary and irreversible step in fertilization which is triggered by sperm receptor, in which the sperm's and ovum's plasma membranes fuse and the sperm penetrates the zona pellucida. Cf Capacitation.
The release of enzymes from the acrosome on the head of the sperm. This process causes the sperm to penetrate the zona pellucida of the egg and begin fertilization.