Compare and contrast the types of digestive system found in worms.

Worms’ digestive systems are almost the same. These worms somehow vary in the anatomy of which some parts are located. Parts that are currently the same for every worm species are mouth, pharynx, intestine and anus, physiologically. Take for instance earthworm, these type of worms have various parts like esophagus, crop and gizzard. Another are round worms, they have pseudocoleom. As observed and typical for these and some worms, their mouth is usually located at the anterior portion of the organism however, for some this linear system of the digestive tract is different for these types of worms. An example is flatworms, they have mouths that are located at bottom of their body near the caudal area. These type of species eat and defecate at one area.     

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