Kids Research Express

. Comb Jellies , a phylum of about 100 widely distributed marine animals resembling jellyfish. The comb jellies have eight rows of comblike plates arranged longitudinally around the body. The plates are moved back and forth in a rippling motion and serve to propel the animal through the water. Most species have two long tentacles at either side of the transparent body, which are used to capture prey. In general the bodies of comb jellies are oval, with a throat opening into the body cavity. They have no separate digestive system, the particles of food being ingested by the individual cells within the body. A sense organ at the opposite end of the body from the mouth is composed of a mass of tiny bony particles, supported away from the body on four legs. Impulses from this organ pass through the legs and into the body of the animal along grooves in the body that contain a large number of hairlike cilia. These grooves, although not true nerves, perform a similar function. Most of the cte

. Ctenophora -> Jellyfish-like marine animals distinguished by eight rows of cilia that propel the body in swimming. They feed on other invertebrates using two retractable sticky tentacles to capture prey. All ctenophores are hermaphroditic and reproduce sexually. Many are luminescent. – Examples: Sea walnuts, comb jellies Platyhelminthes -> Structurally simple worms with no anus or circulatory system. Known as flatworms, their flattened bodies enable internal tissues to be near the skin surface, permitting gas and nutrient exchange with the environment. A muscular layer just beneath the skin layer aids in locomotion. Flatworms are hermaphrodites and reproduce sexually. They typically have a life cycle involving a parasitic larval stage. Many types of flatworms are parasites of vertebrates. – Examples: Flatworms, flukes, tapeworms Mesozoa -> Minute parasitic animals of invertebrates, particularly squids and octopuses. These worms have a simple, elongated, ciliated body. The