PLATYHELMINTH1 - 1 Hermaphroditic adults release eggs into...

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PLATYHELMINTHS (THE FLATWORMS) 1. Trematodes (flukes)---these have flat, leaf-shaped bodies with a ventral sucker and an oral  sucker, which they use to hold themselves in place and to suck fluids from the host. They can  also absorb food through their outer covering, called the cuticle. Their common names are taken  from the tissue in the host where the adults live (lung flukes, liver flukes, etc.).  a.  Clonorchis sinensis--- Chinese liver fluke—this parasite is very common in Asian countries,  but does not spread in the United States because the proper intermediate hosts are not present.  b.  Paragonimus westermani ---lung fluke—this parasite occurs throughout the world, including  the US and Canada. The adult lives in the bronchioles of humans and other mammals. Life cycle:
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Unformatted text preview: 1) Hermaphroditic adults release eggs into the bronchi. Often they are coughed up and swallowed, then excreted in the feces of the definitive host. 2) The eggs must reach water. 3) Inside the egg a larva called a miracidium develops. 4) Larva enters a suitable snail. Only certain species of aquatic snails are suitable. 5) Inside the snail, the miracidium develops into a second larval form, a redia. Rediae undergo asexual reproduction. Each redia then develops into a cercaria. 6) Cercariae bore out of the snail and penetrate into a crayfish. 7) Cercariae develop into a cyst form called a metacercaria in the muscles and other tissues of the crayfish....
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This note was uploaded on 01/23/2012 for the course MCB MCB2010 taught by Professor Smith during the Fall '09 term at Broward College.

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