Oogamy is a form of heterogamy in which the female produced gamete is signifcantly larger than the male gamete. Highly motile sperm participate in the fertilization of the immotile egg. Kaguya is one success from 460 attempts at growing embryos. ... Gametes (in Greek: γαμέτες) —also known as sex cells, or spores—are the specialized germ cells that come together during fertilization (conception) in organisms that reproduce sexually. ... Motility is the ability to move spontaneously and independently. ...