ANIMAL KINGDOM Part-10, NCERT Class-11

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Phylum – Platyhelminthes

• Dorso-ventrally flattened body structure(thats why it is called Flatworms)
• Mostly Endoparasitic
• Bilaterally symmetrical, Triploblastic, Acoelomate
• Flatworms show Body-Level of Organisation.
• In Parasitic form, Hooks and Suckers are present
• Flame Cells help in Osmoregulation and Excretion.
• Hermaphrodite
• Flatworm named Planeria show high regenaration capacity.
• Internal fertilization.
• Development through many larval stages.

Example:
• Taenia (Tapeworm)

• Fasciola (Liver fluke)

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