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List of eleven examples of flagellated protozoans.
Example # 1. Trypanosoma Gambiense:
The parasite of sleeping sickness. It was first observed by Forde in 1901. Fruce discovered that the parasite of sleeping sickness is transmitted by tsetse fly. It causes Gambian sleeping sickness. The disease, also called Gambian trypanosomiasis, is found in western and central parts of Africa.
The parasite is transmitted by blood sucking tse-tse fly, Glossina palpalis. The reserve host is antelope. The parasite does not affect antelope and the fly. Mouth and contractile vacuole are absent. Food is absorbed through the body surface. In human beings the parasite lives in the blood plasma. Later the parasite enters cerebrospinal fluid and damages the brain. It makes the patient lethargic and unconscious.
Example # 2. Trypansoma Rhodesiense:
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It causes Rhodesian sleeping sickness. The disease is also called Rhodesian trypanosomiasis. The parasite is transmitted by the bites of tsetse fly (Glossina palpalis and Glossina morsitans). Initially parasite is present in the blood of man but later on it enters the cerebrospinal fluid.
Example # 3. Trypanosoma Cruzi:
It causes South American trypanosomiasis (also called Chagas disease). The symptoms of the disease are fever, diarrhoea, anaemia and enlargement of lymphoid glands. Human beings become infected by contamination of wounds, etc. with faeces of triatoinid bugs.
Polymorphism in Trypanosoma:
During life cycle trypanosomes multiply and modify into four main types of polymorphic forms which differ from each other in the form of the body and arrangement of organelles.
Example # 4. Leishmania Donovani:
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It causes kala-azar or dum-dum fever (= visceral leishmaniasis). Kala-azar means black sickness. This disease is quite common in East Asia including India, parts of Africa and America.
The fever is continuous and is accompanied by anaemia, enlargement of liver, spleen, etc. The parasite is transmitted by sand-fly, Phlebotomus argentipes and other species. Dogs and cats function as reservoir host. The parasite lives inside the cells of liver, spleen, lymph glands, and bone marrow.
Example # 5. Leishmania Tropica:
It causes skin Leishmaniasis (Cutaneous Oriental Sore). The infected persons may be seen with cutaneous sores on hands, feet, and face. It leads to ulcerated wounds with raised edges. The disease is spread by sand flies. The parasite lives in the endothelial cells of skin capillaries.
Example # 6. Leishmanian Brasilliensis:
It causes mucocutaneous Leishmaniasis (also called Espundia). Espundia is characterized by lesions upon skin and mucous membrane of nose, mouth, pharynx and rarely vagina. The parasite is transmitted by the sand flies.
Example # 7. Giardia Intestinalis (Giardia-lambia):
It is named Giardia after Professor Giard of Paris and lambia after Lambl of Prague who gave a detailed description of the parasite. Giardia is commonly nick named as the “Grand Old Man of Intestine. It occurs in the upper part of human small intestine. Transmission occurs by taking cysts of the parasite with food and water.
There are two nuclei and four pairs (one anterior and three posterior) of backwardly directed flagella. Two supporting needle-like auxostyles are also present. It causes epigastric pain, abdominal discomfort, diarrhoea, headache and sometimes fever. The disease caused by Giardia is popularly known as giardiasis.
Example # 8. Trichomonas Vaginalis:
It inhabits vagina of women and causes the disease leucorrhoea. The disease is characterised by burning sensation, itching and frothy discharge. Transmission is by coition (sexual intercourse). In males infection of urethra and prostate is common.
Example # 9. Trichomonas Hominis:
Resides in the large intestine and causes mild diarrhoea.
Example # 10. Trichonympha Campanula:
This zoo flagellate occurs as a symbiont in the intestine of termites. Trichonympha secretes cellulose digesting enzymes b-glucosidases which convert cellulose into glucose. The digested food is shared by the zoo flagellate and termite. Without Trichonympha the termites starve and die.
Example # 11. Lophomonas Blattarum:
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It occurs as a symbiont in the intestine of wood roaches. Lophomonas secretes enzymes for digestion of cellulose. The digested food is shared by both.
