Fertilization
Fertilization of ovum by sperm in midportion of uterine tube
sperms - own motility - tail
ovum - passive muscle contractions, secretes sperm attractant
50-100 sperms contact zona pellucida
bind to sperm receptor (ZP3)
acrosomal reaction (breakdown of acrosom-lysosome like organelle , release of enzymes; acrosin - penetration of sperm through zona pellucida)