General characteristics of fungi by rk

the fungi

1. RanjeetKumar Taram
M.Sc. I sem(Microbiology)
S.o.S. in Life Sciences
Pt.RavishankarShuklaUniversity

2. Fungi is the plural of the word fungus which is derived from the latin
word FUNGOUR which means to flourish.
The word was primarily used with reference to MUSHROOMS which
develop overnight.
In common language the fungi may be defined as non-green nucleated
thallophytes.
In scientific way ,the fungi are achlorophyllous, non-vascular
thallophytes where reproductive or vegetative structures do not
permit them to be assigned to position among recognised groups of
higher plants or algae.
Today about 5100 genera and and more than 50000 species of fungi
are known. Familiar example of fungi are the yeast,
mold,mushrooms,pufballs,rusts and smuts.

3. Habitat
The fungi are ubiquitous .They are found in almost every available
habitat on earth where organic material is present. Thus they are
universal in their distribution.
Many fungi are terrestrial.Theyoccur in soil which abounds in
dead,decayingorganic materials. The terrestrial fungi thrive best in
humus soil. They produce non-motile reproductive cell which are
dispersed passively by wind,wateror animals.
Some fungi are aquatic . The aquatic fungi are considered primitive.
They live on decaying organic matter and living organisms found in
fresh water and produce flagellated reproductive cells which swim to
new localities.
Exeptthese some fungi are found in drinking water and foodstuff.

4. Habits or mode of life
•The fungi have very varied habits. They are
heterotrophs, because they lack chlorophyll so they
are unable to manufacture their own fooodfrom CO2
and H2O. They obtain food readymade from on
external source.
•The fungi are divided into three groups on the basis
of their mode of life :-
•1.Saprophytes: -A fungus that grows where dead
organic matter abound in the substratum is called
saprophytes.Ex. Mucorsps.
•2. Paracites:-A fungus that live in or on the living
bodies of other organisms and obtain food from
them.

5. •There are three types of paracites:-
•Obligate parasite :-ex. Downy and powdery
mildews.
•Facultative saprophytes:-ex.Phytopthora
infestans-potato blight disease.
•Facultative parasite:-ex. Fusariumsps.
•3. Symbiotic:-when fungus survive with other
organism into partnership and this association
both the partner are mutually benefitted , that
is called synbiotic.
•ex. Mycorhiza–association of fungal hyphae
and hiigherplant root.

6. Somatic phase
•A).Thallus:-A plant body that is not
differentiate into stem, leaves and true roots
and lacks of a vascular system that is called
thallus. It may be unicellular or filamentous.
1.Unicellular thallus:-In some of the lower
fungi such as chytrids, the thallusis more
are less spherical ,single celled structure.
Ex –Synchytrium, yeast.
2.Filamentous thallus:-the vast majority of
the fungi have a filamentous thallus. It
originates through the germination of
spores. The spores gives rise to a fluffy
thallusconsisting of a cottony mass of
fine,branchedfilaments. Ex. –Penicillium
sps.
Unicellular thallus
Filamentous thallus

7. •B) mycelium :-the long fine filament
of fungi are called hyphae and a group
of hyphae is called mycelium. The
mycelium is food procuring structure
en the life cycle.
•Kinds of mycelium :-
•Aseptatemycelium :-the mycelium
in the vegetative phase usually lacks
internal partition of any kind. This
type of hyphae are thus
multinucleated and aseptate. Ex.-
Mucorsps.
•Septatemycelium:-many classes of
fungi develop internal cross walls
called the septa and this type of
mycelium is called septatemycelium.
Ex.-Penicillumsps.

8. C)Structure of Fungal cell:-with the exception of slime molds,
the fungal cell usually consists of a strong, rigid cell wall
enclosing the protoplast.
•The cell wall :-the basic structural constituent of the cell wall
in the majority of the fungi is chitin. It is a polysaccharide
based on the nitrogen containing sugar (glucosamine).
•The protoplast:-the living substance of the cell within the cell
is the protoplast. It is differentiate into cell membrane,
vacuolated cytoplasm, cell organelles and one or more nuclei.

9. •D)Flagella:-the motile cell of fungi are furnished
with one or two fine, protoplasmic ,whip like
thread known as the flagella. It is found in motile
cell of lower fungi(Phycomycetes).
•Three types of flagella:-
Whiplash flagellum with an end piece.
Whiplash flagellum with blunt end.
Tinsel flagellum.

10. Reproductive phase
•When the mycelium has reached a certain stage of maturity
and has accumulated reserve food, it starts reproducing.
•There are a three kinds of reproduction found in fungi:-
Vegetative reproduction-The most
common method of vegetative
reproduction is fragmentation. the
fungi reproduced vegetativelyby
other means, such as fission,
budding, sclerotia, rhizomorphs,
etc.

11. Asexual reproduction-The
asexual reproduction takes place
by means of spores. Different
types of spores are found in
fungi such as zoospore , conidia,
chlamydospore.
Sexual reproduction-A large
number of fungi reproduce
sexually by planogametic
copulation(Synchytriumsps.),
Gametangialcontact(Aspergillus
sps.), Gametangial
copulation(Mucorsps.).

12. Vashishta, B. R., A. K. Sinha, and Anil Kumar.
Botany for Degree Students: Fungi. S. Chand,
2016.
http://www.biologydiscussion.com/essay/essay-
on-fungi-biology/21760