list three major distinguishing features of annelids
13. There are no respiratory organs and the worms breathe through its moist skin. The three classes of Annelids are: Oligochaeta (earthworms); Polychaeta (sand worms); Hirudinea (leeches). Leeches are parasitic and are used by the medical profession to withdraw blood from humans in certain situations.Source(s): ATP-Man Â· 9 years ago. Thumbs up. 5. Thumbs down. 0. 1 comment. Loading .... Bilateral symmetry. 3. True body cavity (coelom) is partitioned by structures called septa. 4. The organs of the digestive, nervous, and circulatory systems penetrate the septa and run the length of the body. 5.
PHYLUM ANNELIDA (segmented worms) The name âAnnelidaâ means âlittle ringâ, which refers to the segments that make up their bodies. As in molluscs, a fluid-filled body cavity, the coelom, is present. Earthworms, leeches, and an assortment of segmented marine worms belong to this phylum.HYLUM ANNELIDA (segmented worms) The name âAnnelidaâ means âlittle ringâ, which refers to the segments that make up their bodies. As in molluscs, a fluid-filled body cavity, the coelom, is present. Earthworms, leeches, and an assortment of segmented marine worms belong to this phylum.