E
The phylum Annelida includes worms that have a true coelom and a complete digestive tract. Annelids, such as earthworms and marine bristle worms, exhibit segmentation and are known for their well-developed body cavities and digestive systems.
aschelminthes
No, mollusks have a true coelom instead of a pseudocoelom. The coelom is a part of mollusks and annelids that is a cavity within the mesoderm that is filled with fluid.
no
Another name for the gut is the gastrointestinal tract (GI tract) or digestive system.
platyhelminthes
platyhelminthes
platyhelminthes
Platyhelminthes have an acoelomate body plan, which means they lack a true coelom. Instead, they have a solid body with a more primitive digestive cavity and lack a fluid-filled body cavity like true coelomates.
The coelom is the body cavity of an animal. A true coelom is a body cavity that is complete from mouth to anus with no breaks; there are animals that have pseudocoeloms - mouths and anuses but no solid connection between the two.
Cnidarians do not have a true coelom (body cavity lined with mesoderm). Instead, they have a simple body plan with a central digestive cavity called the gastrovascular cavity. This cavity serves for both digestion and circulation of nutrients.
The coelom originates from the mesoderm during embryonic development in animals. In protostomes, the coelom typically forms through a process called schizocoely, where the mesoderm splits to create the coelomic cavity. In deuterostomes, it forms through enterocoely, where the coelom develops from pouches that bud off the digestive tract. This fluid-filled cavity plays a crucial role in the organization and functioning of complex body structures.