EXTRA CELLULAR AND FLUID FEEDING

How a filter feeder obtains food:
  • Stream of water carries particles/food
  • In through siphon
  • Mucus on gills traps particles
  • Cilia transport particles/water current (along food groove) towards mouth
  • Enzymes in intestine breakdown food
  • Carbohydrates absorbed as monomers
How a filter feeder creates a feeding current:
  • Cilia
  • Beating/ moving rhythmically
Extra-cellular digestion:
  • Body consists of thin threads (hyphae)
  • Hyphae secrete enzymes that diffuse through wall onto food
  • Enzymes hydrolyse materials in food to monomers
  • Monomers then absorbed into hyphae by F.D. and A.T.
  • In fungi (e.g. saprophytic fungi), cilia not involved in moving food
Summary Table
  Saprophytic fungus Filter feeding mollusc Mammal
Cilia involved in moving food Incorrect Correct Incorrect
Organism prduces digestive enzymes Correct Correct Correct
Carbohydrates absorbed into cells as monomers such as glucose Correct Correct Correct

     

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