The document provides information about the general characteristics and fascinating aspects of fungi. It defines fungi as eukaryotic organisms that lack chlorophyll and have cell walls containing chitin. Fungi can exist unicellular as yeasts or multicellular as molds, and reproduce both sexually and asexually through spores. The document highlights that fungi play important roles in decomposition, relationships with plants, and uses like food and medicine.
2. Table of Content:
Introduction.
General characters of fungi.
The fascinating world of fungi.
Summary.
Reference.
3.
4. 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.
5. 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.
6. 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.
7. 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.
8. General Characters of Fungi:
Possess characteristic storage range of
organic compounds- glycogens, sugar alcohols
and lipids.
9. 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 world's 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.
11. Summary:
[1] Eukaryotic - fungal cells have membrane bound nuclei
and organelles
[2] Heterotrophic - they must absorb organic carboniferous
material to grow and survive, unlike plants which only
need inorganic carbon (CO2) and sunlight to "eat"
[3] Saprophytic - they feed on dead and decomposing
matter
[4] Chitinous cell walls
[5] Spore producing
12. Summary:
[6] The produce hyphae (collectively mycelia)
[7] Most are multicellular or have a multicellular phase
[8] Their visible structures are haploid (half the DNA)
[9] They prefer dark moist environments.
[10] Many can reproduce sexually, but all reproduce asexually.
[11] 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.
