![]() ![]() The cookie is used to store the user consent for the cookies in the category "Performance". This cookie is set by GDPR Cookie Consent plugin. The cookie is used to store the user consent for the cookies in the category "Other. The cookies is used to store the user consent for the cookies in the category "Necessary". The cookie is set by GDPR cookie consent to record the user consent for the cookies in the category "Functional". The cookie is used to store the user consent for the cookies in the category "Analytics". These cookies ensure basic functionalities and security features of the website, anonymously. Necessary cookies are absolutely essential for the website to function properly. To compensate the huge loss during its perilious journey from host to host further multiplication by asexual means has appeared, in addition to the already accentuated rate of multiplication. Twice in its life cycle, the young embryos are exposed to the environment and the cycle which is already full of risks becomes more risky. On the other hand a single fluke may produce about 50,000 eggs. ![]() The reproductive organs are more developed. Jaundice and adenomata have also been reported.ĭue to parasitic life, considerable degeneration of the vegetative organs has taken place in Fasciola. The attack of liver fluke causes ‘liver-rot’, which is disastrous to the host and death has been recorded in most cases of liver-rot. The eggs come out with the faeces about 3 to 4 months (incubation period) after infection. The encysted cercaria known as metacercaria, is taken by the host with the grass and the young fluke on escape, may reach the liver through bile ducts or hepatic portal vein, and grows rapidly to reach the adult stage. The cercaria forces its way out of the snail, loses its tail, becomes encysted and remains attached to blades of grass or other herbage.ġ2. (c) The gonads, glands, etc., begin to appear.ġ1. (b) The anterior and posterior suckers, the mouth, pharynx and a bifid intestine are present. The cercaria escapes through the birth opening of the redia. Cercariae are produced if the season is summer but redia gives rise to a fresh generation of 8-12 rediae if the season is winter.ġ0. From the germ cells in the redia, 14-20 cercariae develop in each redia. (e) A birth opening is situated anteriorly near the circular edge.ĩ. (d) Germ cells are present in the internal cavity. (c) A system of excretory vessel is present. (b) The mouth leads into pharynx and a sac-like intestine is present. (a) The body is cylindrical, with a circular ridge near the anterior end and a pair of short processes near the posterior end. Five to eight rediae are usually formed in each sporocyst. Each cell divides to produce blastula, gastrula and finally a form of larva, the redia.Ĩ. The germ cells of the sporocyst behave like parthenogenetic ova. (c) The internal cavity contains germ cells.ħ. (b) The flame cells and remnants of eye spots are present. (a) Its wall is formed by a single layer of cells. ![]() The ciliated ectoderm is lost, it grows to an elongated sac and forms the sporocyst. ![]()
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