Questions for 12 July 2018 Zoology

Q:-1 Discuss the life cycle of Taenia. Give an account on its pathogenesity. (15)

Q:-2 Discuss the parasitic adaptations of Platyhelminthes. Explain why they have reduced GI tract? (15)

Q:-3 Comment on the characteristics of Platyhelminthes. Classify the phylum upto sub classes. (20)

Q:-4 Compare the process of transcription in eukaryotes and prokaryotes. Enlist all the essential enzymes.

Q:-5 What is RNA editing? Give the details of type 1 splicing.  Why the split genes are primitive characters?



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CANAL SYSTEM IN Porifera

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Canal system in Porifera (sponges) Body of all sponges is the perforated by large number of apertures through which water enters Inside body and flows through a system of criss-crossing canals collectively forming the canal system which is a characteristic feature of poriferans. Following types of canal systems are found in sponges: Ascon type, with flagellated spongocoel Sycon type, with flagellated radial canals Leucon type, with flagellated chambers Rhagon type, with conical shape and broad base ASCON TYPE This is the simplest type of canal system and is found in  Leucosolenia  and other homocoela. Ostia are present on the surface of body and lead directly into the spongocoel, which is lined by flagellated choanocyte cells. Spongocoel opens to the outside through a narrow circular opening, the  osculum  located at the distal free end of the sponge body. Water enters through ostia into spongocoel and goes out of body through the  osculum . SYCON TYPE This type of ca
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Parasitic adaptation of Taenia

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Retrogressive Metamorphosis

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