PHYLUM ROTIFERA

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PHYLUM ROTIFERA

• ROTIFERS

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GENERAL CHARACTERISTICS

• - PSEUDOCOELOMATES
• - 1700 SPECIES
• - TRANSPARENT
• - FREE-LIVING
• - FRESH WATER
• - SIZE 100 - 500 ? (MICROMETRERS)
• - MALES ARE SMALLER THAN FEMALES

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- ROTIFERS CAN SURVIVE LONG PERIODS W/OUT H2O

• STRUCTURES
• - CROWN OF CILIA (USED TO SWEEP FOOD INTO
  DIGESTIVE TRACT)
• - ROTIFERS EAT BACTERIA, ALGAE, PROTOZOA
• - MASTAX (MUSCULAR ORGAN THAT BREAKS DOWN FOOD)

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STRUCTURES CONTD

• -STOMACH
• - NUTRIENTS ARE ABSORBED IN INTESTINE
• - CLOACA
• 1. CHAMBER WHICH COLLECTS UNDIGESTED MATERIAL
• 2. ALSO COLLECTS REPRODUCTIVE EXCRETORY
  SUBSTANCES

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MORE STRUCTURES

• - FLAME CELLS EXCRETORY TUBULES COLLECT EXCESS
  H2O
• - CLOACA EMPTIES OUT THROUGH AN ANUS
• - CEPHALIZATION
• 1. PAIR OF CEREBRAL GANGLIA
• 2. SOME SPECIES HAVE 2 EYESPOETS ON THE ANTERIOR
  END