The biology of the external surfaces of helminth parasites

摘要: The biological properties of the surface helminth parasites are examined under three headings, morphology, digestive-absorptive function and defence. concept host-parasite interface is explored. Platyhelminth covered by a syncytial tegument with sunken parenchymal cell bodies. either microvillous or deeply folded, presenting large area relative to volume. acanthocephalan structurally unique, possessing branching pore-canal system. majority nematodes surrounded thick cuticle composed distinct layers; exceptions include entomophilic nematodes. absorptive discussed published data on transtegumental transport nutrient molecules examined. Most impermeable small molecules, but all other helminths utilise mechanisms. Cestodes acanthocephalans lack gut becomes major site uptake. Surface-bound enzymes have been described in several indicate possible extent digestion parasites. Binding host digestive may also serve protective as well nutritional function. Surface defence mechanisms whereby physiological interactions between parasite at effect evasion host's defences. essence these disguise.