BIO 1106 Chapter Notes - Chapter 37, 38b: Gonopore, Chaeta, Polychaete

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4 Apr 2016
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Class turbellaria: 3,000 species, free-living flatworms inhabiting freshwater, saltwater, and moist terrestrial environments, scavenge and prey on small animals, are hermaphroditic, meaning that individuals have both male and female sex organs. Often called planaria common freshwater turbellarian with typical characteristics of flatworms the head has lateral lobes and sensory organs called eyespots feed by sucking food through its mouth and into a tubular pharynx leading to the gastrovascular cavity. Muscular pharynx is usually retracted in the body but can be everted through an opening in the midventral epidermis (middle of the lower surface) Most digestion in the gastrovascular cavity is extracellular, but phagocytic cells line the cavity and complete digestion of small particles intracellulary. Fasciola: sheep liver fluke, infects sheep, other vertebrates, and (rarely) humans, much larger than opisthorchis, but similar in structure, sucks food (blood, mucus, and cells) through a muscular pharynx located at the mouth.