Taxonomic level: phylum Nematoda; grade of construction: organs derived from three tissue layers; symmetry: bilateral; type of gut: complete; type of body cavity other than gut: pseudocoel; segmentation: absent; circulatory system: present; nervous system: small bundles of nerves (ganglia), two nerve cords; excretion: ...
Are nematodes segmented or unsegmented?
With regards to morphology, nematodes are mostly non-segmented with a cylindrical cross-section with most of them being microscopic (less than one millimeter in length). A majority of the species also have a complete alimentary tract and a well developed nervous system that controls the cell muscles.
Where do you see segmentation in a nematode?
Segmentation or Metameric Segmentation is the repetition of elements of the main organ systems of the body along the length of the body.