1. Round Worms, Flat Worms and Annelids Andrew Sahr

2. Characteristics  Roundworms:  Nemathelminths phylum  Range from microscopic to as long as 3.3 feet (1 meter).  Have a hard, sharp spear on their head, and some have bristles on the head  Protected by a flexible but strong, grooved body covering  A layer beneath this covering releases fluids that harden to form the covering  Bilaterally symmetrical

3. Cont.  The body has 3 tissue layers and a fluid-filled false body cavity, meaning the cavity is between the inner and middle layers rather than the middle layer and the outer layer, as it is in complex animals  Roundworms live in salt water, fresh water and the soil.  Many of them are harmful to man as they are parasites.

5. Roundworm Life Cycle  Starts as an egg in a feces of an animal  Another animal either eats that animal or the feces of that animal  Transfers into the animals own intestines  Molts into the lava  Larva migrates through the intestinal wall and into the lungs where its coughed up and swallowed once more  Once it returns to the larva it begins to mature as an adult.

7. Reproduction  Sexually  Most species have a separate male and female but some are hermaphroditic  Males are typically smaller  Females have ovaries for holding the egg  During the copulation, male protrudes one or more spicules out of the cloaca and insert them into genital pore of the female.

8. Reproduction Cont.  Amoeboid sperm cells are passed along the spicules into the female worm  Eggs can be either embryonated or unembryonated when passed by the female, which means that their fertilized eggs are not yet developed

9. Roundworms in our Area  Baylisascaris  Intestinal Raccoon roundworm  Effects animals, including humans  Mature in Raccoon intestine  Released eggs take 2-3 weeks to become infective  When we ingest them from soil or water they hatch into larvae inside us  Travel through the body  Affect our organs and muscles

10. Characteristics cont.  Flatworms: also known as flukes  Bilaterally symmetrical  Body has 3 layers of tissues with organs and organelles  Body contains no internal cavity  Possesses a blind gut (i.e. it has a mouth but no anus)  Has Protonephridial excretory organs instead of an anus

11. Cont.  Reproduction is mostly sexual as hermaphrodites  Mostly feed on animals and other smaller life forms  Some occur in all major habitats, including many as parasites of other animals  Bilaterally symmetrical

13. Life Cycle of Flatworms  Start as an egg  Passed out in the feces of a bird  Eaten by Whelks  Inside the larvae hatches the eggs and multiplies by budding  Leave and invade cockles  Infected cockles are eaten by the birds in which the flukes mature and lay there eggs

15. Reproduction  A flat worm is reproduced when it splits In two  It will immediately form a new flatworm  Hermaphroditic  Each individual produces sperm and egg  When two flatworms mate, they exchange sperm so both become fertilized.  can also reproduce asexually by transverse fission

16. Reproduction Cont.  The body constricts at the midsection, and the posterior end grips a substrate  body rips apart  Each half grows replacements of the missing pieces to form two whole flatworms  if one of these flatworms is cut in half, each half will regenerate into two separate fully- functioning flatworms

17. Flatworms in Our Area  Heterobilharzia americanum  Waterborne flatworm  Parasite  Affects mostly dogs and raccoons  Sexually reproduces in the intestines  Eggs are laid in there so they can be carried out through feces

18. Characteristics cont.  Annelids:  Bilaterally symmetrical  Body has more than two cell layers which are tissues and organs  Body possesses a through gut with mouth and anus  Has true closed circulatory system  Has no true respiratory organs  Lives in most environments  Feed a wide range of material  Reproduction normally sexual and gonochoristic or hermaphoditic  Includes earthworms and leeches

20. Life Cycle of Annelids, The Earthworm  Hermaphrodites.  When two earthworms mate  They lie together and cover themselves in sticky mucus  Pass sperm into each others bodies  Sperm makes the egg in each body grow  A thick ring of slime forms around each worm's body and as the earthworm wriggles forward  the ring with eggs inside it slips off and is left on the ground  The ring closes at both ends and becomes a hard cocoon that protects the eggs.

21. Cont.  The eggs hatch after two weeks if the weather is warm  They can take up to three months to hatch when it is cold  Usually one or two earthworms hatch out of each egg  The young worms are about 12 millimeters long and light pink in color  Earthworms are able to mate when they are twelve months old.

22. Reproduction  Asexual  by dividing into two or more pieces or by budding off a new individual while the parent remains a complete organism  Some reproduce all asexually, while some reproduce sexually as well  Leeches have never been seen reproducing sexually

23. Annelids in Minnesota  Earthworms  All terrestrial earthworms are not native to Minnesota  15 species have been identified so far  Glaciers would have killed any worms before the European settlements  First Earthworms probably arrived through soil and plants from Europe

24. Sources  http://animals.jrank.org/pages/1551/Roundworms-Adenophorea-PHYSICAL-CHARACTERISTICS.html http://animals.jrank.org/pages/1551/Roundworms-Adenophorea-PHYSICAL-CHARACTERISTICS.html  http://www.earthlife.net/inverts/annelida.html http://www.earthlife.net/inverts/annelida.html  http://www.earthlife.net/inverts/platyhelminthes.html http://www.earthlife.net/inverts/platyhelminthes.html  http://www.getridofthings.com/get-rid-of-roundworm.htm http://www.getridofthings.com/get-rid-of-roundworm.htm  http://www.teara.govt.nz/en/marine-animals-without-backbones/2/3 http://www.teara.govt.nz/en/marine-animals-without-backbones/2/3  http://www.ento.csiro.au/education/allies/annelida.html http://www.ento.csiro.au/education/allies/annelida.html  http://www.cdc.gov/ncidod/dpd/parasites/baylisascaris/factsht_baylisascaris.htm http://www.cdc.gov/ncidod/dpd/parasites/baylisascaris/factsht_baylisascaris.htm  http://local.petmd.com/Waterborne_Flatworm_Parasite_in_Dogs_Detroit_Lakes_MN-r1331428- Detroit_Lakes_MN.html http://local.petmd.com/Waterborne_Flatworm_Parasite_in_Dogs_Detroit_Lakes_MN-r1331428- Detroit_Lakes_MN.html http://local.petmd.com/Waterborne_Flatworm_Parasite_in_Dogs_Detroit_Lakes_MN-r1331428- Detroit_Lakes_MN.html  http://www.dnr.state.mn.us/invasives/terrestrialanimals/earthworms/index.html http://www.dnr.state.mn.us/invasives/terrestrialanimals/earthworms/index.html  http://www.localriding.com/image-files/roundworm-cycle.gif http://www.localriding.com/image-files/roundworm-cycle.gif  http://www.dpd.cdc.gov/dpdx/images/ParasiteImages/A-F/Dioctophymiasis/Dioctophyme_LifeCycle.gif http://www.dpd.cdc.gov/dpdx/images/ParasiteImages/A-F/Dioctophymiasis/Dioctophyme_LifeCycle.gif  http://petcaregt.com/blog/wp-content/uploads/2008/11/round-worm.jpg http://petcaregt.com/blog/wp-content/uploads/2008/11/round-worm.jpg  http://staff.tuhsd.k12.az.us/gfoster/standard/nematod.gif http://staff.tuhsd.k12.az.us/gfoster/standard/nematod.gif  http://www.cartage.org.lb/en/themes/sciences/zoology/biologicaldiverstity/AnimalsI/flatworm.gif http://www.cartage.org.lb/en/themes/sciences/zoology/biologicaldiverstity/AnimalsI/flatworm.gif  http://www.starfish.ch/Fotos/worms-Wuermer/plathelminthes-Plattwurm/Pseudobiceros-gloriosus3.jpg http://www.starfish.ch/Fotos/worms-Wuermer/plathelminthes-Plattwurm/Pseudobiceros-gloriosus3.jpg  http://www.mcwdn.org/Animals/Roundworms.html http://www.mcwdn.org/Animals/Roundworms.html  http://www.kidcyber.com.au/topics/worms.htm http://www.kidcyber.com.au/topics/worms.htm