Roundworms, also known in biology as nematodes, belong to the group of parasites that are recognized as free-moving. Scientists have long proven that they are the primary type of molting species. In the animal kingdom, nematodes are considered one of the most diverse groups.
Different kinds
A huge variety of nematodes lives in both soil and water. Their important role in the functioning of ecosystems is known. There is a similarity and difference between roundworms of different species, each of which has its own special place in nature. The main ones include: human roundworm, pinworm, human whipworm, cryogenic head, necator, cinerea , trichinella and rishta.
The similarity and difference of roundworms of different species
Nematodes have similarities in both internal and external structure:
- bilateral symmetry;
- all types of nematodes are three-layer animals;
- roundworms belong to multicellular animals;
- they have an unsegmented body;
- all nematodes move equally in space;
- the body cover consists of longitudinal muscles, a single-layer epithelium and a dense cuticle;
- parasites also have the same type of digestive tract, which is through with the anus.
As you can see, there are many similarities in different types of roundworms. Although nematodes have differences, they are not numerous:
- some species of three-layer animals prefer a free habitat;
- some types of worms can exist only in another organism - they belong to parasites (ascarids can be an example).
Round and flat worms
It is worth noting the similarities and differences of roundworms of different species and flat invertebrates.
Their similarities:
- both types of worms can be parasites in the internal organs of animals;
- neither round nor flat parasites have a respiratory and circulatory system;
- they can breed both with eggs and larvae;
- the worms have an epithelium, on the surface of which muscle fibers are located;
- they have much in common in the structure of the nervous system.
These parasites have a rather large number of important similarities; the differences between worms of different species and thin invertebrates are no less significant.
Their differences:
- the main difference between these two types is the method of reproduction, because roundworms belong to gender, and flatworms are classified as hermaphrodites;
- parasites also have different body shapes;
- they have different types of digestion;
- flatworms and nematodes have different muscle systems and the number of species.