Chapter 15 - general characteristics of nematoda

cryptobiosis

state of hybernation similar to cyst forms

free living nematode example

caenorhabditis elegans

Parasitic nematodes

hookworms, pinworms, trichinosis, elephantisis, river blindness

Nematode sexual dimorphism

smaller males, posterior end or male is curved, males have copulatory organs

Nematode body cavity

pseudocoelom

Nematode characteristics

non segmented, bilateral, cylindrical

Nematode molting

occurs four times

nematode life cycle

egg, four larval stages, two adult stages

Nematode nervous system

4 nerve ganglia and 6 longitudinal nerves

Nematode circulatory and respiratory system

absent, rely on skin

Nematode excretory system

excretory canals

Nematode reproduction

oviparous, viviparous

Oviparous nematode

Ascaris, trichocephal

Viviparous nematodes

trichinella, dracunculus, and filarial nematodes

Intestinal nematodes common names

hook worms, large intestinal roundworms, pinworm & seatworm, trichina worm

Intestinal nematodes scientific names

Necator americanus, ancylostoma duodenale, ascaris lumbricoides, enterobius vermicularis, trichinella spiralis

Blood and tissue nematodes

filarial worms, dracunculus medinensis, trichuris trichiura