Friday 11 December 2015

FUNGI KINGDOM

* Fungus are heterotrophes,they depend on dead and decayed food, hence they are saprophytes. some are parasites, some are symbionts e.g.- Lichen( live in association with algae) and some are mycorrhiza( association with roots of higher plants).
* fungus are cosmopolitan and occur in air, water, soil  and on animals and plants body.
* they prefer to grow in warm and humid area.
* only yeast are unicellular.
*fungus are filamentous.
*their bodies consist of long slender thread like structure called hyphae.
*the cell wall of fungi is composed of chitin and polysaccharides.
* all types of reproduction are seen in fungus, such as
         >vegetative reproduction-by fragmentation , fission, and budding.

         >asexual reproduction-by spore formation called conidia or sporangiospores or zoospores.

         >sexual reproduction-by oospore, ascospore and basidiospore.

*sexual reproduction involves following steps-
         -fusion of protoplasm between two motile and non-motile gametes called plasmogamy.         -fussion of two nuclei called karyogamy.         -meiosis in zygote resulting in haploid spores.

* dikaryon- in ascomycetes and basidiomycetes, at the time of fusion the two nuclei comes together and makes dikaryon. this phase is called dikaryophase..
* fungus are divide into various classes, some are-
    1. phycomycetes
    2.ascomycetes
    3.basidiomycetes
    4.deuteromycetes

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