Phylum Nematoda
Roundworms

Ex. Trichinella, hookworm, pinworm, heartworm

Nematos - threadlike

Over 25,000 known species

Parasitic and free-living

Found in every habitat on earth

Characteristics of Phylum Nematoda

Body Type: Bilateral Symmetry

Body Organization: TriploblasticThree tissue layers

Endoderm, Mesoderm, Ectoderm

Body Cavity: Pseudocoelom

bodycavities

Ecological Roles:Parasitic: Affect both plants and animals

Food source

Aerate soil

Decomposers

lamelle-460

Digestive System:Complete digestive system (mouth and anus separate)

Specialized organs for breakdown and absorption of nutrients

nematode.jpgReproduction:Sexual: Dioecious (sexes separate)

Asexual: None

Circulation: Diffusion

Nervous System: Ganglion (brain), dorsal and ventral nerve cords & sensory organs

Respiration: Diffusion through skin

Excretion: anus & tubes

Trichinella (Undercooked pork)

Parasitic Nematodes

Filarial wormLLymphatic or Subcutaneous Filariasis

Hookworm

hookworm.jpg