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Ali and his friends went to a popular restaurant in Doha. Ali asked the waiter to bring him the best fish dishes because he likes sea food. After they wrapped up their food they thanked Ali for the invitation and they went to their homes. At night, Ali felt uncomfortable and severe diarrhea and weakness in all the body. Ali went to the hospital and his Doctor diagnosed his illness by parasitic injury caused by Tapeworms. Ali did not understand what is meant by the disease. Few persons realize that there are more kinds of parasitic organism in the world. In general the parasitic way of life is so successful that it has evolved independently in nearly every phylum of animals. The discovery and description of new parasite species continues until now. There is no wonder that the science of parasitology has developed out of efforts to understand parasites and their relationships with their hosts . Ali asked his doctor loudly , is there huge worms in my stomach ! . Most people regards these animals derives from facts that tape worms live in intestine and are only seen when they are passed with the host feces and has difficult cure . The scientific approach increased the understanding of tape worms and shown that they are one of the most fascinating groups of organisms in the animal kingdom . Although it's unique in the living organisms, but has bad risks to human health. Many examination of process, cause and effects of tapeworms shows that it's has the most dangerous diseases that influence human life.
Parasitology is largely study of symbiosis or literally living together. In wider term as originally proposed by the German scholar Aderem de Bary in (1879) any two organisms living in close association, commonly one living in or on the body of the other, are symbiotic, as contrasted with free living. Symbiotic relationships can be characterized further by specifying the nature of interaction between the parasites. phoresis exists when two symbionts are traveling together. There is no physiological or biochemical dependence on the part of either participant. Usually one phoront is smaller than the other and is mechanically carried about by its larger companion. Examples are bacteria on the legs of fly or fungal spores on the feet of a beetle. Mutualism describes a relationship in which both partners benefit from each other. Mutualism is usually obligatory, since in most cases physiological dependence has evolved to such degree that one mutual can't survive without the other. For example, cleaning symbiosis is a behavioral phenomenon that occurs between certain crustacean's small fish and larger marine fish .in commensalism one partner benefits from the association, but the host is neither helped nor harmed. The term means eating at the same table. Many commensal relationships involve feeding on wasted or otherwise not consumed by the host. If the parasites live on the surface of its host, it is called an ectoparasite; if internal it's endoparasites. Most parasites are obligate parasites that are they cannot complete their life cycle without spending time in a parasitic relationship. some parasite live their entire adult life on their host it's called permanent parasites , whereas intermediate parasite such as a mosquito or bed bug only feeds on the host blood . "The host is an island invaded by strangers with different needs, different food requirements, different locations within which to raise progeny " W.Taliaferro (1867) . parasitology differentiates among various types of host according to the role the host play in the life cycle of the parasite . A definitive host is one in which the parasite reaches sexual maturity . an intermediate host is one that is required for parasite development but does not reaches sexual maturity . In conclusion, Parasitism is a relationship in which one of the participants either harm or lives at the expanse of the host .
According to CDC( 1877) there are 4.46 billion of human infected with helminthes. Few of many kinds of parasites that infect human addition to causing many deaths. Cestoidea or tapeworm is phylum from helminthes. strobila of cestodes is a structure unique among other phylum . Typically it consists of linear sets of reproductive organs which called proglottid . After proglottid are fully developed eggs it's said to be gravid . when segment reach the end of it is strobila , it often detaches and passes out of the host feces . Most tapeworms have head or scolex at the anterior end that may be equipped with a variety of holdfast organs that function to maintain the position of animal body. A scolex may bear suckers, grooves and hooks to penetrate the gut wall of the host. Cestodes lack any trace of a digestive tract and therefore must absorb all required substance through their external covering. thus, structure and function of the body covering have been of great interest to parasitologists . Before 1960 the body covering of cestodes was unknown, but it is now known that is a living tissue with high metabolic activity which called tegument. The membrane of cestode tegument projects out toward the host as numerous finger shaped tubes called microtriches . "He was as fitted to survive in this modern world as tapeworm in an intestine" William Golding (1969). Microtiches serve to increase absorptive area of tegument in the intestine. Most tapeworms are hermaphroditic its means has both sex organs and are capable of fertilizing their own eggs. Mature tapeworms may live for few days or up to many years depending on species. During its reproductive life a single worm produces from a few to millions of eggs, each with potential of developing into adult. In conclusion most species of cestodes are parasites of wild animals, and few infect humans.
The diversity of cestoide is an astonishing and the study of their many varieties of life cycle is a science in itself." We should all brush up on tapeworms from time to time " Dave (19766, p339). Hymenolepis nana commonly called the rate tapeworm . The life cycle of H. nana is unique among tapeworm in that an intermedatiate host is optional. When eaten by a person or a rodent. Eggs hatch after passed in the host feces in the duodenum releasing onchsheres which penetrate the intestine wall of intermediate host for example flea or beetle and became cycsticercoid . After ingestion by the final host human or rate by food contamination. In five to six days cysticercoids developed in the small intestine to mature adult that capable to produce eggs. Genus Echinococcus contains the smallest tapeworms. However, their juveniles often from huge cysts and are more capable of infection humans, resulting in very serious disease in many parts of the world. Echinococcus granulose or dog tapeworm mainly effect dog which is the final host that produce infective eggs. Sheep or cows serve as intermediate host after ingestion the hydatid cyst will occur in the muscle or in the liver. In some cases dog bit or attack sheep that infected by hydatid cyst that will developed in to adult worm in dog intestine. The life cycle of Taenia solium is the same of Taenia saginata except that its intermediate hosts are pigs instead of cattle. Gravid proglottids passed in feces that contain infective eggs . When eaten, oncosheres develop into cysticerci in muscles and other organs. Infection of T. solium and saginata has been elevated in the California city ( Adams , 1988 ) . When a fish eats an infected copepod, the procercoid is released and bores its way through the intestinal wall and into the body muscles. Here it absorbs nutrients and grow rapidly into aplercocercoid that will effect human or animals that eaten undercooked food. Aplercocercide will grow and developed into Diphyllobothrium latum or fish tapeworm . In conclusion, there are great hazards obstructing of transmission and development of each worm of cestode