ANIMAL KINGDOM Part-7, NCERT Class-11

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Phylum-Porifera

• Commonly known as sponges.
• Generally marine,  mostly asymmetrical.
• Multicellular, cellular level of organisation.
• Primitive animals.
• Water Transport System or Canal System present.
• Water enters the body cavity/central cavity through minute small pores named Ostia and goes out through a big pore named Osculum 
• Canal system helps the poriferans in food gathering, respitory exchange, waste removal etc.
• The central cavity is known as Spongocoel which is lined by Choanocytes or Collar cells. 
• Intracellular digestion
• Body of poriferans are supported by Spicules or Spongin fibres.
• Hermaphrodite (sex is not seperate)
• Asexual reproduction -  Fragmentation
Sexual Reproduction - Gamete Formation 
• Internal fertilization
• Indirect development
• Possess larval stage that is morphologically distinct from the adult stage

Example:
• Sycon(Scypha)
• Spongilla(Fresh Water Sponge)

• Euspongia (Bath sponge)






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