FLATWORMS, ROUNDWORMS, AND SEGMENTED WORMS

Worms

(Lexy Bishop, Kellie Black, and Violet Lawson)

Flatworms

Phylum Name: Platyhelminthes

Diversity: 20,000 species

General Characteristics of Flatworms

Bilaterally symmetricalSimplest animals- has three tissue layersMove in several waysNervous system is complex

Body Support or Skeleton/Movement

(Flatworms)

Uses cilia on its ventral surface to search for food

Muscles enable it to twist and turn

Has eyes that spot light

Reproduction and Digestion

Reproduction Sexual- cross-fertilization Asexual- fragmentation and regeneration

Digestion In the gastro vascular cavity Single opening Nutrients distributed to cells that line cavity Finely branched (The gastro vascular cavity)

Examples of Animals in this Phylum

FlukesTapeworms

Roundworms

Phylum Name: NematodaDiversity: 15,000 species

General Characteristics of Roundworms

CyndricalComplete digestive tractPointed headsTwo OpeningsTapered Tails

Body Support or Skeleton/Movement

Exoskeleton-cuticleHas to be shedMuscles are longitudeCausing thrashing movements

Reproduction and Digestion

Reproduction: Sexual: separate males/females Internal fertilization

Digestion: Specialized regions Complete digestion tract

Examples of animals in this phylum

HookwormsPinwormsThreadworms

Segmented Worms

Phylum Name: AnnelidaDiversity: 15,000 species.

General Characteristics of Segmented Worms

Segments similarDistinct head and tailDigested tract is not segmentedHas a nerve cord and 2 main blood vesselsClosed circulatory system

Body Support or Skeleton/Movement

Fluid-filledTwo sets of musclesCircular and longitude

Reproduction And Digestion

ReproductionSexual- the male and female

structures are present Internal fertilization

DigestionSpecialized regionsComplete digestion tract

Examples of Animals in this Phylum

SandwormsEarthwormsParasitic leaches