Final answer:
A typical Gono zooid in cnidarians like the Obelia matures several medusae for sexual reproduction, with reproductive cells undergoing meiosis to produce gametes for genetic diversity. The medusae break free, mate, and the cycle continues with planula larva developing into polyps.
Step-by-step explanation:
In the reproductive cycles of cnidarians like the Obelia, the Gono zooid is responsible for asexual budding, which ultimately produces sexually reproductive medusae. A typical gonozooid will mature several medusae at a time, though the exact number can vary. Within the reproductive buds, the developing medusae will eventually break free and mature into free-swimming organisms that are capable of sexual reproduction, being either male or female (dioecious).
Within each medusa, the reproductive cells undergo meiosis within their respective gonads—testes or ovaries—culminating in the production of gametes, sperm or eggs, respectively. This process ultimately contributes to the genetic diversity of the population and ensures the continuity of the species through sexual reproduction. After mating, the resultant zygote develops into a larva called planula which then settles and transforms into a sessile polyp, thereby completing the life cycle.