Because Annelids have much more "complicated" characteristics such as, The body possesses 3 separate sections of themselves, have a closed Circulatory system, and has a nervous system with an interior nerve ring, ganglia & ventral cord. As nematodes and Platyhelminthes have very simple characteristics:
Nematodes: Bilaterally symmetrical, feeds on just about everything, lives just about anywhere, and has no circulatory system.
Platyhelminthes: do not have an anus, have a sac-like body, contain a hydrostatic skeleton and sexually reproduce.
There's many of them, but here are some of the bigger ones; Annelids, unlike roundworms (or flatworms for that matter) are segmented. That is after all how they get their name (annelida = little ring). Annelids also have a very complex organ system. Roundworms only possess a reproduction system as they usually live in an organism's intestines and don't need to digest food. Annelids posses both a reproduction system, and a digestive system as well as a circulatory system. As they are true coelomates their organs and organ systems are organised rather than just kinda' being tossed in there. =)
The animals which don't have vertebral column are called invertebrates. They are 1) poriferans 2) Coelenterates 3) Platyhelminthes 4) Nematyhelminthes 5) Annelids 6) Arthropods 7) Molluscs 9) Echinodermates
Did you know, potentially life-endangering parasites can live in the human body for up to several decades? Moreover, these parasites, known as blood flukes, have the ability to regenerate themselves. And so, can survive in hostile environments. Furthermore, these worms belong to Phylum Platyhelminthes. Let us explore this phylum. visit our page : theconvergencetech .com
Yes, meiosis is more complex than mitosis because it involves two rounds of cell division and results in the formation of gametes with half the number of chromosomes.
In eukaryotes, DNA synthesis is expected to be more complex than in bacteria because eukaryotic cells have larger and more complex genomes, with multiple linear chromosomes and additional regulatory mechanisms. This complexity requires more intricate coordination of DNA replication processes in eukaryotic cells compared to bacteria, which typically have simpler circular genomes.
Annelids are segmented whereas roundworms are not. Annelids have a true coelom while roundworms have a pseudocoelom. Annelids have a more complex nervous system than roundworms. Annelids have a more complex circulatory system than roundworms.
Nematodes are roundworms. Many of the 28,000 or more species of nematodes are parasitic. Nematodes are very successful organisms, living just about everywhere where there is life.
Annelids are the first animal phyla to have a true body cavity (coelom), which is enclosed by mesoderm. This cavity enables more complex organ systems and allows for greater specialization of body functions.
Brief answer only. Phyllum Platyhelminthes are the flatworms. These have three layers of cells. Phyllum Annelidia are the segmented worms. These have blood vessels, a developed nervous system, and a digestive system organized round a central tube.
There's many of them, but here are some of the bigger ones; Annelids, unlike roundworms (or flatworms for that matter) are segmented. That is after all how they get their name (annelida = little ring). Annelids also have a very complex organ system. Roundworms only possess a reproduction system as they usually live in an organism's intestines and don't need to digest food. Annelids posses both a reproduction system, and a digestive system as well as a circulatory system. As they are true coelomates their organs and organ systems are organised rather than just kinda' being tossed in there. =)
No, flatworms are multicellular organisms with a simple body plan, but they do not have many cells compared to more complex organisms. They typically have around a few thousand to a few million cells.
Platyhelminthes, commonly known as flatworms, exhibit bilateral symmetry. This means their bodies are organized in such a way that they can be divided into two mirror-image halves along a single plane, typically through the central axis. This type of symmetry is associated with a more complex body structure and allows for directional movement and the development of a centralized nervous system.
Over 17,000 species of annelids have been discovered.
yes and they may lay more than 200,000 a day
One of the first animals to develop a true body cavity was roundworms, also known as nematodes. This body cavity, called a pseudocoelom, helped provide support and structure to their bodies, allowing for more efficient movement and organ function.
Nematodes are triploblastic (they have an ectoderm, mesoderm and endoderm) but also have a pseudocoelom (a closed fluid-containing cavity that acts as a hydrostatic skeleton to maintain body shape, circulate nutrients, and hold the major organs). They have a thick cuticle covering their body to protect them from digestion. Just inside their gut are the longitudinal muscles; unlike other worms (annelids), the nematodes lack a circular muscle and so their movement is restricted to a side-to-side whip. The female reproductive system consists of two highly folded ovaries and two oviducts that store eggs Annelids (other worms) are also triploblastic. They are coelomate where the coelom is divided into segments and each segment can move independently. The most distinguishing feature of this group is segmentation, with the segments visible as rings around the body. Movement is by their circular muscles which expand and contract, moving the animal forward as well as side to side. Movement is also aided by the presence of bristles along the body. So basically the main difference in the two phylum is the presence or lack of circular muscle which is an important evolutionary step in annelids as it allows more effective movement.
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.