Overview of Earthworm Anatomy
An earthworm is an invertebrate animal. An invertebrate animal is an animal without a backbone. An earthworm feeds on dead and live organic matter and is usually found in soil. It is tube shaped with neither legs nor hands and interestingly, its digestive system runs from its mouth to the anus, which is basically the length of its body. It uses its skin for respiration. There are two ways to look at the anatomy of an earthworm; external anatomy or internal anatomy. The external anatomy of the worm includes the features of the worm which you can see with your naked eye or by the use of lens before the worm is dissected or cut open. In short, these are the features on the outside of the worm. These features are: segment, mouth, prostomium, anterior end, peristomium, clitellum, satae, sperm grooves, tubercula pubertatis, posterior, dorsal, ventral, periproct, epidermis and sperm duct opening. They have different body colours but are mostly dark red, muddy green and red-v...