Brood pouches are located on the upper part of a medusa jelly fish's oral arms. the female's eggs attach themselves to brood pouches located on the upper part of her oral arms surrounding her mouth. Then when she swims through the male's sperm the eggs become fertilized.
The fertilized eggs then leave the stomach and attach themselves to a female's oral arms.
During a Jellyfish's life cycle, they experience an alternation of generations. One generation, called the medussa, reproduces sexually. Another Generation, called the polyp, reproduces asexually. The medusa form is the dominant and most recognized form of the jellyfish nowadays. Overall, the basic stages in the life cycle of a jellyfish include:
egg and sperm
planula larva
polyp
polyp hydroid colony
ephyra
medusa
Jellyfish reproduce sexually, meaning that adult jellyfish are male or female. Gonads, are the reproductive organs of both sexes. The gonads in males produce sperm, while females produce eggs. When jellyfish are ready to mate, the male releases sperm through its mouth opening located on the underside of its bell. The fertilization of eggs in the female jellyfish depends on the species.
In some species, the female's eggs attach themselves to brood pouches located on the upper part of her oral arms surrounding her mouth. Through the swimming process, chances that a female swam through sperm fertilizes it. the eggs are kept in the mouth and the male's sperm swims into her stomach, where it fertilizes the eggs. The fertilized eggs later leave the stomach and attach themselves to the female's oral arms. After the fertilized eggs have went through the process of embryonic develoment, they hatch. The free-swimming planulae that are born then leave the female's mouth or brood pouch and set out on their own.