Note: This is BR’s first true essay. It represents a paragraph a day after a week of prior research. Grammar learned: colons, writing out numerals below 11, singular vs plural agreement.
Taxonomy is the way scientists classify animals. Worms are broken into three Phyla: Nematoda, Annelida, and Platyhelminthes. Platyhelminthes are also called flatworms. Unlike the other classes of worms, flatworms can reproduce by splitting apart. The second class of worms is Nematoda. They are also called roundworms. Most roundworms are one to two mm long. Annelida are also called segmented worms. Some live in the ground and some live in the deep-sea.
The simplest group of worms is Platyhelminthes. Their pharynx is like a proboscis. When the worm is ready to eat, the pharynx goes out of the mouth and sucks up all the food. They do not have an anus. When the food is digested, they spit out the excess. They live in wet areas- for example: puddles, the ocean, your lungs and in your intestines. They can cause death.
A slight bit more complex than Platyhelminthes is Nematoda. They are unsegmented worms. They are usually found with white coloring. They are parasitic. Unlike the Platyhelminthes, they do have an anus. The body has no segments and has no cilia. The mouth opens into an oral cavity. Nematoda has a true digestive track.
The most complex phyla is the Annelida. Marine annelids are often called tubeworms or segmented worms. They can gt up to six cm in width, two cm in diameter, and one meter in length. The body will have over 150 segments. It does have an anus like the Nematoda. And when you think of a worm, this is what you think of. Earthworms and vent orms are Annelids. You commonly find them in your yard.
These phyla of worms are all similar because they all use cilia to move. They are all different because they all have different shapes: tube worms are like ribbed socks; round worms are like skinny pieces of string; and flatworms are like pieces of ribbon. However these strange phyla must all be in a moist environment.