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Platyhelminthes/Flatworms. Protosome -Protozoa. Structures. Inside No circulatory system A. Diffusion No Respiratory organs A. Diffusion for respiration 1. Makes them vulnerable to fluid loss, therefore live in water No anus
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Platyhelminthes/Flatworms Protosome-Protozoa
Structures Inside • No circulatory system • A. Diffusion • No Respiratory organs • A. Diffusion for respiration • 1. Makes them vulnerable to fluid loss, therefore live in water • No anus • A. Regurgitate undigested material through the gastrovascularcavity, pharynx, and mouth • Nervous system • A. Simple brain • 1. Ganglion-simple bundles of nerves • ventral nerve cord-run down each side of flatworm Outside • Multicellular • Bilaterally symmetrical • Unsegmented • Flattened • Soft Bodies
General Reproductive mechanism • Asexual • Transversal Bipartition • regenerate their tissues • Sexual • Hermaphrodites • Have both male and female parts
Groups/Examples • Subgroups • Turbellaria • Largest of the three • Monogenea • No more than two cm in length • Trematoda • No more than two cm in length • Examples • Tapeworms • Planaria • Flukes
Feeding Mechanism Parasitic Free living • Monogenea, and Trematoda • Feed off of a host • Infect blood and organs of host • Including humans • Have a pharynx that pumps food into gastrointestinal cavity • Heterotrophs • Turbullerians • Capture Prey • Most are carnivores • Have a pharynx that pumps food into gastrointestinal cavity • Heterotrophs • Prey on: • annelids, arthropods, mollusks, and tunicates
Distinguishing characteristics • No internal cavity • Acoemorphic • Organs have direct contact with the epithelium
Nematodes/Roundworms Protosome-Ecdsozoa Domain: Eukaryotic Kingdom: Animalia Phylum: Nematoda
Structures • Inside • No circulatory system • diffusion • Nitrogenous waste excretes through body wall • form of ammonia • no specific organs • Four peripheral nerves • Run the length of the body • Ventral nerve -largest • Combines both sensory and motor • Dorsal nerve -motor control • Lateral nerves-sensory • Smaller nerves -supply the sensory organs of the head • Reproductive system • Have distinct males and females • Males find females and mate • Males are usually smaller than females • Outside • Multicellular • Cylindrical • Bilateral Symmetry • Head is radially symmetrical • sensory bristles • Adhesive 'caudal gland' • found at the tip of the tail
Groups/Examples • Subgroups • Class Dorylaimea • Class Enoplea • Class Secernentea • Subclass Diplogasteria • Subclass Rhabditia • Subclass Spiruria • Subclass Tylenchia • "Chromadorea“ *Examples • Vinegar eels • Caenorhabditiselegans • Toxocaracanis • Hookworms
Feeding Mechanism Parasitic Free living • Oral cavity with cuticle • Hookworms, Pinworms, Whipworms • Feed mostly on humans and household animals • Trichina worm • Feed on rats, pigs and other animals • Oral cavity • Four molts of the cuticle • Play important role in the decomposition process • Feed on: • Algae • fungi • small animals • fecal matter • dead organisms • living tissues.
Distinguishing characteristics • Thick cuticle that covers body • Above epidermis layer • can be shed for growth • two or three distinct layers
Power Point by Angelicka^2 http://en.wikipedia.org/wiki/Nematode#Reproduction http://en.wikipedia.org/wiki/Flatworm http://www.wetwebmedia.com/flatworms.htm