Can you give 5 unique characteristics about a flatworm?

Flatworms, or platyhelminthes, exhibit several unique characteristics: they have a flattened body shape that enhances diffusion of gases and nutrients, lack a circulatory and respiratory system, and possess a simple nervous system with a pair of cerebral ganglia. Many flatworms are hermaphroditic, containing both male and female reproductive organs, allowing for versatile reproduction. They also exhibit a remarkable ability to regenerate lost body parts, making them a subject of interest in biological studies. Lastly, some flatworms are parasitic, possessing specialized adaptations to thrive within their hosts.