EXCRETORY SYSTEM

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EXCRETORY SYSTEM
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EXCRETORY SYSTEM

• Boundaries of the system - tiny tubes for liquid
  removal, large areas to store solid waste.
• Input into the system - extra water, used food
  and by-products of food metabolism.
• Output of the system - urine-like liquid and
  feces
• Interactions with other systems - removal of
  liquid waste from the blood

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EXCRETORY SYSTEM

• Components of the excretory system
• Nephridia - small curly tubes coming out from
  under the intestine on each segment, they give
  off liquid waste to the skin, can be seen with
  hand lens.
• Rectum last inch or so of the intestine which
  has no typhlosole, used to store feces.

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RESPIRATORY SYSTEM

• The respiration of the worm is performed using
  only the skin as the organ of gas exchange.
  Worms are thin enough so that they may not need
  gills or lungs. The skin of a worm must be moist
  for the gas to pass through. If the skin is
  totally wet, or if the worm is in water it will
  not be able to breathe and will suffocate.

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REPRODUCTIVE SYSTEM

• Worms are classified as hermaphrodites. This
  means that there is no such thing as a male or a
  female worm. They have both male and female
  parts in one body, but they may not fertilize
  themselves. Nature has made it impossible for
  them to use their own eggs and sperm to make a
  baby worm because they could form a retarded or
  malformed offspring. Humans are not legally
  allowed to marry brother, sister or cousins for
  much the same reason.

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REPRODUCTIVE SYSTEM

• When mating, the worms attach themselves, trade
  sperm and then separate. Later the mucus forms
  into a cocoon. The worm begins to slip backwards
  out of the mucus ball. As it is passed backward,
  the mucus passes over the female genital pore and
  the eggs are released into the cocoon. As it
  continues to pass forward, the sperm are released
  from the male genital pore. The sperm fertilize
  the eggs and the cocoon slip off the anterior end
  of the worm. The edges of the mucus ball
  constrict and a cocoon is formed. Although many
  eggs are deposited into the cocoon, only one worm
  will develop which will emerge in 3-4 weeks.

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REPRODUCTIVE SYSTEM
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REPRODUCTIVE SYSTEM

• Boundaries of the system - All reproductive
  organs, and skin.
• Input into the system - eggs, sperm, and mucus.
• Output of the system - baby worms! )
• Interactions with other systems - all other
  system must be created for the baby worm during
  its development in the cocoon

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REPRODUCTIVE SYSTEM

• Components of the reproductive system
• - Ovaries- not seen, produce eggs (female sex
  cells)
• - Testes- cannot be seen, they make sperm (male
  sex cells)

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REPRODUCTIVE SYSTEM

• Seminal receptacles- store sperm traded from
  other worm
• Seminal vesicles- stores worms own sperm before
  trading
• Sperm groove - Groove line in skin which helps
  guide sperm to its
• mate

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REPRODUCTIVE SYSTEM

• Male genital pores- hole which lets out sperm
• Female genital pores- invisible hole which
  release eggs
• Clitellum- ring around the worm used to make
  mucus for reproduction

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REPRODUCTIVE SYSTEM
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Nervous System

• The nervous system of the worm has only two
  parts, the brain ganglia and the nerve cord. The
  nerve cord is a tan line running on the ventral
  side of the worm under the intestine. The brain
  consists of two small ganglia or knots of nerves
  which wrap around the pharynx.

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Nervous System

• Brain Ganglia
• Nerve Cord