What are the adaptive features of trematodes?
The cercariae are adapted for dispersal in space and exhibit a large variety in morphology. They are adapted to recognise and penetrate the second intermediate host, and contain behavioural and physiological adaptations not present in earlier life stages.
What are Monogenetic trematodes?
The trematodes are a group of organisms that are related to the planarian of biology class. The monogenetic trematodes are parasites of amphibians, fish, and other hosts, and are only important if their eggs are found in the feces of a cat that has eaten an infected host.
How are monogeneans different from most other parasitic flatworms?
The life cycle of monogeneans also differs from the life cycle of tapeworms and trematodes. Monogeneans have a direct life cycle, which means they go directly from host to host (fish to fish). Tapeworms and trematodes have an indirect life cycle that often requires multiple hosts (different types of animals).
What are adaptive features?
An adaptive feature is an inherited feature that helps an organism to survive and reproduce in its environment.
How is the Cercariae adapted to its environment?
The behaviour patterns can be interpreted as adaptations to: (1) dispersal by leaving the habitat of the snail intermediate host and distribution within the area; (2) long survival by energy saving swimming behaviour, by avoiding responses to inappropriate stimuli, by selecting favourable microhabitats and probably by …
What do you mean by Monogenetic?
Definition of monogenetic 1 : relating to or involving monogenesis. 2 : of, relating to, or being any of a class (Monogenea) of flatworms that ordinarily live as ectoparasites on a single host (such as a fish or amphibian) throughout their entire life cycle.
Which is Monogenetic parasite?
Monogenetic parasite is the one which completels its life cycle in one organism only.Example is Entamoeba histolytica which lives in human large intestine.It passes on the cycts through excreta or stool.The cysts when ingested by another individual through contaminated food or water ,will enter in to the intestine of …
Do trematodes have alimentary canals?
* The alimentary canal of trematodes is covered by a single layer of epithelial cells. * Depending on the species, trematodes may have secondary or tertiary branches of the intestine. * Apart from lacking a body cavity, trematodes also lack a respiratory system.
How is the lifecycle of a Monogenetic fluke different from an Digenetic fluke?
– Additionally, if an organism can complete its life cycle inside a single host it is termed as monogenetic while if an organism utilises two host organisms for completing its life cycle it is termed as digenetic organisms. – Liver flukes spend their life cycle utilising two hosts.
What are the characteristics of Cestodes?
Cestodes are long, flat, ribbon-like organisms commonly called tapeworms. The head, or scolex, has one or more hooked suckers for firm attachment to the host. Behind the head is the neck which is the growing region. The body consists of segments, each containing reproductive organs.
What are the characteristics of Monogenea?
Monogeneans lack respiratory, skeletal, and circulatory systems and have no or weakly developed oral suckers. Like other flatworms, Monogenea have no true body cavity (coelom). They have a simple digestive system consisting of a mouth opening with a muscular pharynx and an intestine with no terminal opening (anus).
What is a monogenetic trematode?
Monogenetic trematodes are usually ectoparasites of fish, amphibians, and reptiles. They attach to the exterior surfaces, such as gills, skin, fins, and the mouth. These trematodes attach to the host with a posterior adhesive organ that may have suckers, hooks, or clamps ( Figure 7-2 ).
What are trematodes and what are they good for?
Trematodes significant for dogs belong to the Digenean subclass with a mollusk intermediate host mandatory in the life cycle. Some species require a second intermediate host—a fish, for example. Digenean trematodes are not too specific in their definitive host demands and many carnivores are suitable.
What are trematodes (flukes)?
Trematodes (flukes) include parasitic flatworms belonging to the phylum Platyhelminthes, class Trematoda, and subclasses Aspidogastrea (two orders, four families) and Digenea (ten orders, more than seventy-two families).
What is the structure of a trematode?
Structurally, trematodes are flat and elongated worms whose outer surface (tegument) contains microvilli that both protect the worm and act as a nutrient absorptive surface. Adult worms possess anterior and ventral suckers, which are useful in maintaining attachment to host tissue.