In tunicates, sexual reproduction occurs through individuals that are what?

• A. Hermaphrodites
• B. Dioecious
• C. Parthenogenetic
• D. Asexual-only

Answer: (A)

In tunicates, sexual reproduction is typically carried out by individuals that are hermaphrodites. This means a single animal has both male and female reproductive organs and can produce both eggs and sperm. For these sessile, filter-feeding organisms, having hermaphroditic individuals increases mating opportunities: any one individual can contribute gametes to the population, and fertilization occurs when eggs and sperm meet in the surrounding water. The resulting embryos develop into free-swimming larvae that can disperse to found new colonies. While some tunicates can be dioecious or reproduce asexually in colonial forms, the common mode of sexual reproduction involves hermaphroditic individuals.