Eathworms

Earthworms (also known as angleworms) argon any one of the everyplace 1,800 species of terrestrial worms who are members of the phylum Annelida, class Oligochaeta. on that point are 17 native species and 13 introduced European species of earthworm in the unify States. The most common earthworm in the U.S., L. terrestris, grows to about 25 centimetresa, although some species grow as long as 3.3 meters. Earthworms basin be found almost everywhere where the moisture and organization of the soil are appropriate to sustain them.
Only a handful of the earthworm species are in the genus Lumbricus. There are 32 described native earthworms in the Pacific states alone. There are over 20 introduced lumbricids, plus many introduced megascolecids. This is an English language Wikipedia, not a US one, so US-only selective information should be used sparingly.
Digestion and excretion
The earthworm has a simple digestive system compared to other creatures. It possesses an esophagus, which serves the same purpose as it does in higher animals: to carry food. However, the worm esophagus leads to the tame and gastric mill rather than to a stomach (which earthworms do not possess). The crop and gizzard combined serve the purpose of a human race stomach. The crop holds food while the gizzard grinds it down mechanically.



The gizzard leads into the intestine, which follows the length of the earthworms body to the anus. This passage from communicate -> esophagus -> crop -> gizzard -> anus constitutes the entire digestive system.
The lumbricids deplete this pattern but it is not the only one. roughly earthworms cook the gizzard in the anteriormost segments, and many have no gizzard at all. The primary function of the esophageal region in most earthworms (including the lumbricids) is calcium carbonate secretion. The usual patterns are below.
Mouth>pharynx>gizzard>esophagus>intestine
Mouth>pharynx>esophagus>crop>gizzard>intestine
Mouth>pharynx>esophagus>intestine

Most of the earthworms segments possess a pair of excretory organs known as...If you want to get a upright essay, order it on our website: Orderessay



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