Earthworms are hermaphrodites since they can generate both sperm and eggs. Mating involves 2 earthworms inseminating each other where sperms are exchanged. The male and female sexual cavities are located near the clitellum. They connect the lower ends of their anteriors with heads positioned in reverse directions. Mucous secreted joins the openings with slime. Sperm is pushed into the longitudinal channels formed by the mucous. They reach the sperm receptacles

Phyla and Parasites Ten Phyla: Phylum Mollusca ~ Living Species Number: World: at least 50,000; United States: Approximately 20,000; Texas: More than 2,000; Number of Fossil Forms: 150,000 Phylum Brachiopoda ~ Living Species Number: World: 400; United States: 80; Texas: 10; Number of Fossil Forms: 5,000 Phylum Echinodermata ~ Living Species Number: World: 7,000; United States: Approximately 2,000; Texas: Approximately 200; Number of Fossil Forms: 13,000 Phylum Chordata ~ Living Species Number: World: More than 60,000; United States:

Structure of Animals Two animal phyla that can be compared and contrasted are Nematoda and Annelida. Nematoda are roundworms. There are more than 15,000 known species, with scientists estimating there may be as many as half a million species yet to be discovered (Waggoner, 2009). Nematoda have a worm-like appearance outside and a simple internal body structure. The phylum Annelida includes earthworms and their relatives, leeches, and a large number of

Kingdom: Animalia Phylum: Nematoda Part 2: Answer the following questions as they relate to the nine phyla in the assignment table. (Porifera, Cnidaria, Nematoda, Arthropoda, Platyhelminthes, Annelida, Mollusca, Echinodermata, and Chordata.) 1. Which phyla lack organs? What type of symmetry do they have? Porifera and Cnidaria lack organs. Porifera lack any symmetry hence these are asymmetrical while Cnidaria have radial Symmetry. 2. List all of the phyla that show cephalization. The phyla that show cephalization are

Living organisms are subdivided into 5 major kingdoms, including the Monera, the Protista (Protoctista), the Fungi, the Plantae, and the Animalia. Each kingdom is further subdivided into separate phyla or divisions. Generally "animals" are subdivided into phyla, while "plants" are subdivided into divisions. Kingdom of Protista Brown Alga Scientific Classification Kingdom Protista Division Heterokontophyta Phaeophyceae Orders Dictyotales Desmerestiales Fucales Laminariales (kelps) etc. The Brown algae are a large group of multi-cellular algae, including various sorts of seaweed. Their distinctive greenish-brown color comes from the

Like most other animals, the artic fox's cot changes to reflect the summer arctic habitat, becoming a brown or gray color that matches the summer environment (National Geographic, 2008). The photograph by Norbert Rosing (National Geographic, 2004), demonstrates the usefulness of the animal's camouflage: (Norbert Rosing, National Geographic, October, 2004, online at http://ngm.nationalgeographic.com/ngm/finaledit/0410/,2008). The artic fox contributes to the balance of nature because its diet includes rodents, which have a