<p> Name: ______Date: ______Unit 7 Notes #3 - Phylum Platyhelminthes: Flatworms A) Body Plan: - All have ______</p><p>-______: Concentration of sensory organs and nervous tissue at the anterior end of the body (______). </p><p>-Well-developed ______layer called the ______between the ectoderm and endoderm. -Mesoderm includes: ______-Possess an ______: single opening (mouth/anus) to the gastrovascular cavity; use mouth to ingest food and use mouth to expel undigested wastes. B) Diversity: 1. Class ______: -______-Incomplete gut -No suckers or hooks -Ciliated epidermis Example: ______</p><p>2.Class ______: -______-Incomplete gut -______-Outer Cuticle (tegument) Example: ______</p><p>PLANARIA FLUKE</p><p>3. Class______: -______</p><p>-______-______and ______together form a ______for attachment to host -Body consists of repeating sections called ______</p><p>Example : ______C) ______Common To Most______Flatworms:</p><p>1) Parasitic flatworms often have suckers and hooks for attachments, form a structure called a ______.</p><p>2) ______(______) for protection so as </p><p>______or destroyed by the host. 3) Loss of digestive system in some (tapeworms) – these will ______</p><p>______nutrients through ectoderm. 4) Complicated life cycle with the production of many eggs and/or offspring and</p><p>______</p><p>D) Characteristics Of Common Platyhelminthes Members:</p><p>1. ______a. Digestion: Feed on small animals and the remains of larger dead animals.</p><p>-______/______is located mid-way along the ventral surface </p><p>(______) it acts to push food into the gastrovascular cavity.</p><p>-______are present in the pharynx and gastrovascular cavity (they secrete enzymes to digest food) -Gastrovascular cavity will also circulate nutrients and oxygen to various parts of the body. -Indigestible wastes are eliminated out of the mouth.</p><p> b. Nervous : -______</p><p>-A pair of ______run the length of a nervous system. -Connect to a pair of ______(a group of nerve cells) in the anterior end. -Show cephalization with a variety of sensory cells. -Sensory cells are sensitive to ______and various ______. c.______: -______are located below the ectoderm. -The outer layer of ______muscle that constrict the worm, making it ______and ______.</p><p>-Next layer uses ______muscles to ______the worm.</p><p>-There is also a third layer that runs ______(______) and makes the worm a little flatter.</p><p> d. Locomotion: -Body moves by co-ordinating its muscles and ______</p><p>______trail that it secretes from glands in the epidermis. </p><p>-______on the ventral epidermis assists in gliding.</p><p>2. ______</p><p> a. Digestion: -They are______.</p><p>-Mouth present in the middle of the </p><p>______</p><p>-The pharynx swallows the host’s tissues and bodily fluids (blood) into its </p><p>______b. Circulation and Respiration</p><p>-Gastrovascular cavity for circulation and respiration. -They live in tissues that are well supplied with nutrients and oxygen by the host’s blood. c. ______: - ______but they lack most of the special sensory cells found in Planaria.</p><p> d. ______: -Similar to planaria, ______on the ventral epidermis 3. ______a. Digestion: -Have______.</p><p>-Attach themselves to the lining of the host’s intestine by ______</p><p>______</p><p>Tapeworm’s Scolex</p><p>-Worm feeds by absorbing digested food. -Have a modified epidermis called a ______, this thicker skin prevents them from being digested. b) Circulation: -Receive oxygen from blood vessels in the host’s intestine.</p><p>-When oxygen is not available, ______</p><p>E) Reproduction In These Three Common Members of Platyhelminthes:</p><p>1. Planaria: -Reproduce ______-Missing parts will ______</p><p>-Can also reproduce ______</p><p>-______(contains both sexes in one individual), but requires reciprocal exchange of sperm and eggs between two individuals.</p><p>2.______: -Also hermaphrodites</p><p>-Complex life cycle with numerous larval stages that______</p><p>______</p><p>3. ______: - Constantly ______new body sections (______) posterior to its scolex. -Each proglottid contains both male and female reproductive organs. -Mature proglottids with ______</p><p>______-Often have larval stages that infect a number of different hosts Advances of the Platyhelminthes Over the Cnidaria</p><p>1. Platyhelminthes have their ______and even had some simple systems.</p><p>2) Unlike the previous two Phyla (Porifera and Cnidaria), the ______</p><p>______with the development of the middle layer (the mesoderm). The mesoderm has also provided for better muscle development and thus has resulted in an animal that moves around more efficiently.</p><p>3) As a result of moving around, platyhelminthes have further ______</p><p>______</p><p>4) Cnidarians had a nerve net for conducting impulses, but the Platyhelminthes have ______into two longitudinal nerve cords. (______).</p><p>LIVER FLUKE lifecycle</p>