Animalia
Porifera, Platyhelminthes, Nematoda PORIFERA- Porifera are a phylum mainly made up of sponges. They came about around 600 million years ago. A sponge is basically a filter that is alive and has attached itself to a rock, etc. Sponges take on water in which microscopic plants and animals are in and filters them out for food. Sponges draw their prey in by current caused by cells equipped with flagella along the inner wall of the animal. Sponges also have no mouth or any organs. The cells that make up the body of a sponge have definite places and groups of cells have definite jobs. The simplest sponges are nothing more than a tube with an opening at one end. Many sponges live in the ocean. The live grouped in colonies with other sponges. They reproduce by budding, but some species and varieties reproduce sexually.
PLATYHELMINTHES- The phylum platylminthes includes flat worms, flukes and tapeworms. These animals have muscle bands for movement and a mouth for both eating and excreting waste products. Platyhelminthes have both male and female reproductive organs. These animals like to live around moist plants. The flatworms in this phylum were one of the first animals to have bilateral symmetry. Flatworms have a digestive cavity that is simply a branched off sac. They have a definite head which surrounds their tiny little brain. Flatworms are also the first organisms to have their bodies controlled by body organs. Unfortunately for humans, most of the flatworms are parasites, and many of the hosts are humans.
NEMATODA- The phylum nematoda includes mainly roundworms. There are more than 3 million nematodes in every acre of soil! In one handful of dirt, there are usually around 100,000 individual nematodes. Most of these animals are harmless and only feed on other nematodes and small microorganisms. On the other hand, some or parasites of plants and animals like platyhelminthes. There are at least fifty species of nematodes that are parasites of people. Most roundworms are much more primitive than earthworms. Unlike earthworms they have no nervous system or any type of complicated body structure. They have lean, cylinder like bodies like earth worms have and they even have a mouth at one end of their body and an anus at the other end. Nematodes are covered with a thick cuticle that protects them from dirt, if they are free living nematodes or digestive juices if they are parasites. All free living roundworms are very small and look like strings of thread. Parasitic nematodes are much larger and can reach the length of a person's arm. They have no organs or any sense of taste, touch or smell.
MOLLUSCA- The phylum mollusca is made up of snails, slugs clams, squids and octopuses. The first mollusk showed up on earth about 600 million years ago. The members of the phylum mollusca look very different, yet they have a lot in common. All of them have mantles that cover their bodies and secrete shells. All animals in the phylum mollusca have well-developed digestive tracts along with developed hearts, kidneys, and some sort of brain or central nervous system. Most molluscs have heads and sensory organs.
ANNELIDA- This phylum consists of mostly segmented worms. There are about 8, 500 different types of annelids including types of earthworms, bristle worms, and leeches. These animals live in almost every kind of environment. Annelids have segmented bodies which actually consist of a tiny room inside their bodies.
ARTHROPODA- Eighty percent of the animals on earth are a member of the phylum arthropoda. Some of these are lobsters, crabs, barnacles, mites, millipedes, spiders, insects and many other lesser-known animals. Over a million different species have been discovered by scientists and more and more are being discovered all the time. Annelids and arthropods evolved from the same ancestors. Both of these groups have segmented bodies. Arthropods have a harder and thicker "light" cuticle towards the center of their bodies. Worms moved about by use of paddles while arthropods evolved legs and used legs for animation and movement. Arthropoda are the only phylum to have evolved fairly efficient breathing systems. They also have highly developed nervous systems. They have complicated sense organs such as eyes, and antennae. When these animals grow to a certain size they must grow or pop out of their exoskeleton and grow a new one.
Mollusca, Annelida, Arthrooda
Echinoderms and Chordata ECHINODERMS- Members of the echinoderm phylum are starfishes, sand dollars, sea cucumbers, sea urchins, and sea lilies. Echinoderms are slow moving creatures when they are adults. They live mostly on the ocean floor. The ancestors of echinoderms were bilateral at one time, or so is believed by scientists. Modern echinoderms are radial symmetrical. Most echinoderms have internal skeletons that are made up of numerous lime plates. Echinoderms have well-developed cavities inside their bodies sort of like humans. This protects their internal organs from movement of the body. Echinoderms have separate sexes, so the eggs and the sperm are released into the water.
CHORDATA- Chordates appeared on the earth about 570 million years ago. This group of creatures was very efficient at getting food into it's mouth but not very good at getting food from it's mouth to it's stomach. Because of this gill slits evolved allowing the animal to swallow and digest it's food more efficiently. Gills are paired slits on the side of a chordates mouth that allow water which is carrying food to be swept into the chordate's mouth and down it's throat more efficiently. Millions of years later, the gill slits on chordates evolved into also being used for aspiration (breathing) in water. Chordates are the beginnings of what evolved to become fish, sharks, etc.

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