platyhelminthes Flashcards
Describe the tissue layers of platyhelminthes.
triploblastic, acoelomate
What type of body symmetry is present in platyhelminthes?
bilateral
What is cephalization?
concentration of nervous tissue and sensory structures at anterior end of body
What are the function of flame cells?
maintain fluid balance, excretion secondary role
Name the main classes of platyhelminthes.
turbellaria, trematoda, cestoda
What are the distinguishing features of turbellaria (planarians)?
free living, carnivorous
What are the distinguishing features of trematoda (flukes)?
endoparasitic, oral suckers, cuticle
Name a common liver fluke that can be found in humans.
clonorchis sinesis
List the life cycle of the clonorchis sinesis (liver fluke).
Adult in human, miracidia eggs in feces, miracidia ingested by snail, sporocyst, rediae, cercaria free swim to fish, cercaria develop into metacercaria cysts, eaten by human and larvae released from cysts
What stages of the life cycle of a fluke does it reproduce sexually?
adult
What stages of the life cycle of a fluke does it reproduce asexually?
sporocyst, redia
What are the distinguishing features of cestoda (tapeworms)?
endoparasitic, no mouth or gastrovascular cavity, scolex with hooks for attachment, segmented into proglottids
Where are the newest (immature) proglottids found in the body of a tapeworm?
nearest to the scolex
What is a gravid proglottid?
a fertilized proglottid ready to drop off tapeworm body and exit host through feces
