Platyhelminthes vs. Nematoda
Types of Protostomes
Platyhelminthes and Nematoda Definitions
Platyhelminthes vs. Nematoda
Platyhelminthes is a group of invertebrates that are flatworms; on the other hand, Nematoda is a group of invertebrates that are roundworms. Platyhelminthes comprised of the plane and erect body; on the flip side, Nematoda comprised of a cylinder-shaped body that pointed at either end. Platyhelminthes are the acoelomate animals; on the flip side, Nematoda are the pseudo coelomate animals. Platyhelminthes lack a complete digestive system; on the opposite side, Nematoda contains a digestive system as a whole.
Platyhelminthes do not have hard cuticle covering; on the flip side, Nematoda has a hard outer covering called the cuticle. Platyhelminthes belong to superfamily Lophotrochozoa; on the other hand, Nematoda belongs to superfamily Ecdysozoa. Platyhelminthes contain thrashing movements; on the flip side, Nematoda contains gliding movements. Platyhelminthes cause certain diseases like lung flukes, liver flukes, and schistosomiasis; on the other hand, Nematoda causes certain diseases like hookworm disease, trichuriasis, and ascariasis.
Platyhelminthes have three further classes, such as Turbellaria, Trematoda, and Cestoda; on the other side of the coin, Nematoda has two further classes, such as Adenophorea and Secernentea. Platyhelminthes do not contain true body cavity like coelom; on the other hand, Nematoda contains false body cavity coelom.
What are Platyhelminthes?
Platyhelminthes is the type of invertebrate phylum that contains only the flatworms that have a flat body and posture. Platyhelminthes are the type of triploblastic animals with three germinal layers having the bilateral symmetry. But it has an unsegmented body.
Platyhelminthes also show spiral cleavage. They are the acoelomate that does not have the true body cavity like coelom. Like the body cavity, Platyhelminthes also do not contain the complete digestive system. It usually lacks the mouth and the stomach in its digestive system.
The gastrovascular cavity acts like the functions of the stomach. All the other systems of the body, such as respiration and other processes occur by the simple mechanisms. The proper circulatory system of the body is absent in Platyhelminthes. The respiration process occurs through the surface of the body by simple diffusion mechanisms. The excretory system in Platyhelminthes is mainly flame cells that are associated with the Protonephridia.
Platyhelminthes mainly reproduces by asexual methods such as fragmentation. It further subdivided into three classes of Turbellaria, Trematoda, and Cestoda. The presence of Platyhelminthes in different hosts as a parasite causes certain diseases. It includes lung flukes, liver flukes, and schistosomiasis.
What are Nematoda?
Nematoda is the type of invertebrate phylum that contains only the roundworms that have a cylindrical body that tapered at both ends. It is the unsegmented type of worms. Nematoda is the triploblastic animal having three germinal layers with bilateral symmetry. Nematoda also shows a determinate type of cleavage. Nematoda are multicellular, motile, and heterotrophic animals.
They are the pseudo coelomate that has a false body cavity like the coelom. But it contains the complete digestive system, but a well-defined head is not present in Nematoda. But a mouth is present at one end of the worm. The outer covering of the body contains a hard cuticle. Nematoda is the type of worm that has a total of seven stages, such as eggs, four larval stages, and two adult stages.
Nematoda contains almost all types of specialized organ systems. Nematoda also includes free-living and may act as a parasite. Nematoda also reproduces by the sexual and asexual methods. Some are dioecious having both gametes in one body, and some are hermaphrodites. They exhibit simple spiral cleavage. Nematodes further subdivided into two classes which are Adenophorea and Secernentea.