Earthworm

Earthworms are a part of the kingdom Animalia, The phylum Annelida, the class Oligochaeta, and the order Megadrilacea. Earthwork reffers to a broad group of species. All earthworks have a full degestive tract, and have segmented bodied. Segmented bodies refer the the lines you can see on an earth worms. These lines are really where two segments meet. These semgment are the same structure repeated all the way down the worm's body. If they lose a segment, then thaey can even grow it back. Earthworms reproduce sexually, and all earthworms carry both male, and female reproductive organs. They don't have  an internal skeleton or an exoskeleton. They instead maintain their structure with fluid-filled chambers that function as a hydrostatic skeleton. Earthworms move by shortening, and lengthening their bodies.

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Wikipedia

Content Sources:
Wikipedia