EVERYDAY SCIENCE

Detailed explanation-1: -Segmented Worms: Phylum Annelida.

Detailed explanation-2: -Approximately 16, 500 species have been described in phylum Annelida. The phylum includes earthworms, polychaete worms, and leeches. Annelids show protostomic development in embryonic stages and are often called “segmented worms” due to their key characteristic of metamerism, or true segmentation.

Detailed explanation-3: -The annelids include earthworms, polychaete worms, and leeches. All members of the group are to some extent segmented, in other words, made up of segments that are formed by subdivisions that partially transect the body cavity. Segmentation is also called metamerism.

Detailed explanation-4: -Arthropoda is the animal phylum with the highest species diversity, and the majority of animals present in the world belong to this group. It is characterized by a segmented body that remains protected within an exoskeleton and comprises jointed appendages. Thus, this phylum is characterized by segmentation.

Detailed explanation-5: -A segmented body plan is one in which repeated body units are arranged along the anterior–posterior axis, each unit containing elements from a number of organ systems. Segmentation is found in three phyla: the arthropods, annelids, and chordates.