What are the major features of the annelids?
Characteristics of Phylum Annelida
- They have a long and segmented body.
- Annelids are bilaterally symmetrical.
- They are triploblastic.
- Also, they exhibit organ system grade of organisation, showing organ differentiation.
- The body is covered with a thin cuticle.
- They are coelomate.
What is unique about the body of annelids?
Annelid, phylum name Annelida, also called segmented worm, any member of a phylum of invertebrate animals that are characterized by the possession of a body cavity (or coelom), movable bristles (or setae), and a body divided into segments by transverse rings, or annulations, from which they take their name.
What complex body features do annelids have that they share with us?
Annelids are distinguished by ring-like external bands along their muscular body wall that coincide with internal partitions dividing their bodies into segments. With a circulatory system to distribute blood and oxygen and a one-way gut, their bodies are enormously more complex than modern flatworms.
What are the external features of annelids?
External features. The body of an annelid is often described as a tube within a tube. The inner tube, or digestive tract, is separated from the outer tube, or body wall, by the coelom. The head region (prostomium) is followed by a series of segments similar to each other in appearance.
What are the characteristics of a trochophore?
trochophore, also called trochosphere, small, translucent, free-swimming larva characteristic of marine annelids and most groups of mollusks. Trochophores are spherical or pear-shaped and are girdled by a ring of cilia (minute hairlike structures), the prototroch, that enables them to swim.
What kind of body does annelids have?
All annelids have a worm-shaped, segmented body, but one main difference among them is the number and organization of bristles and appendages. Annelids are bilaterally symmetrical, triploblasts, and protostomes.
What are the characteristics of a Trochophore?
What are the two major characteristics that set annelids apart from flatworms?
In addition to a more specialized complete digestive system, annelid worms have also evolved body features not found in flatworms or nematodes. These features appear in some form in all larger, more complex animals: a coelom, a body cavity between the digestive tube and the external body wall that is lined with tissue.
What is the most distinguishing characteristic of annelids Why is it important?
What is the most distinguishing characteristic of annelids? Why is it important? Segmentation; each segment has its own muscles that lengthen and shorten for efficient movement; groups of segments may take on specific function.