General charactersistics of fungiPresentation Transcript
Table of Content: Introduction. General characters of fungi. The fascinating world of fungi. Summary. Reference.
INTRODUCTION: DEFINITION: FUNGI IS A GENERAL TERM WHICH IS USED TO DESCRIBE A GROUP OF EUKARYOTES CHARACTERISED BY THE ABSENCE OF CHLOROPHYLL AND BY THE PRESENCE OF RIGID CELL WALL. THEY CAN EXIST EITHER AS UNICELLULAR IN THE FORM OF YEAST OR AS MULTICELLULAR IN THE FORM OF MOULD.
General Characters of Fungi: Fungi are eukaryotes – possess membrane bound organelles They can exist both as unicellular and multicellular. They are avascular. Most fungi grow as tubular filament – hyphae . A connected mass of hyphae is called mycellium.
General Characters of Fungi: Protoplasam of hypha (cell) is surrounded by rigid cell wall - The walls of hyphae are reinforced by chitin. The fungal cell wall contains ergosterol rather than cholesterol. Fungi produce a unique form of tubulin in connection with nucelar division. Fungi have a unique biosynthetic pathway for synthesis of lysine. Fungi have a small nuclei with very little repetitive DNA. Mitosis occur without dissolution of nuclear membrane.
General Characters of Fungi: All are acholorophylous - Fungi are never autotrops because they don’t have cholorophyll or choloroplast. May be free living or in intimate relationship - Fungi are usually found as opportunistic saprophytes or in some parasitic or symbiotic relationship with anyother autotrops. Fungi reproduce both sexually and asexually - Fungi reproduce by spore, budding or fragmentation. Spores can be both by the means of asexual or sexual reproduction.
General Characters of Fungi: Possess characteristic storage range of organic compounds- glycogens, sugar alcohols and lipids.
The facinating world of Fungi: Fungi are.......... Extraordinary organisms which are neither plants, nor animals. One of the most important group of organisms on this planet Some of the worlds largest and possibly oldest individuals Hallucinogenic magic mushrooms Some are silent killers with deadly poisons. A vital ingredient in beer and bread. Decomposers, essential for natural recycling, helping to guarantee life on earth. Miracle cures for disease. Indispensible partners for many plants.
The fascinating world of fungi:
Summary:  Eukaryotic - fungal cells have membrane bound nuclei and organelles  Heterotrophic - they must absorb organic carboniferous material to grow and survive, unlike plants which only need inorganic carbon (CO2) and sunlight to "eat"  Saprophytic - they feed on dead and decomposing matter  Chitinous cell walls  Spore producing
Summary:  The produce hyphae (collectively mycelia)  Most are multicellular or have a multicellular phase  Their visible structures are haploid (half the DNA)  They prefer dark moist environments.  Many can reproduce sexually, but all reproduce asexually.  Zygotic meiosis - this means that there is only one diploid cell in the organisms life cycle, and that is the zygote which forms from the fusion of two haploid gametes and immediately undergoes reduction division (meiosis) to form haploid cells, which reproduce by mitosis and generate a multicellular fungus. Virtually any part of any fungus that is visible to the naked eye is haploid.