FOR SEM 2 CC3 OF SKBU

1. DR SUJIT GHOSH
GENERAL ACCOUNT AND
CLASSIFICATION
FUNGI BODY PLAN, NUTRITION AND CELL WALL,
CELL STRUCTURE, REPRODUCTION
DR SUJIT GHOSH
J K COLLEGE
PURULIA

2. Fungi are organisms that are grouped in a distinct kingdom within the
eukaryotes. This kingdom includes diverse organisms ranging from
microorganisms such as yeasts or moulds to large multicellular
mushrooms.
What is fungi?
In ShortIn Short
1. Avascular thalloid Eukaryotic,,
2. body made up of tubular branched or unbranched
filament –hyphae .
3. A connected mass of hyphae is called mycellium
spore-bearing
4. heterotrophic organisms that produce extracelluar
enzymes and absorb their nutrition or are parasites

3. Body plan:
Reduced thallus
Unicellular
(yeast)
Thallus: hypha,
mycelium,
Septate
Limited tissue
differentiation
and division of
labor;
In somatic and
reproductive
structures
Tissue form
Filamentous
(dimorphic =
both)
Amoeboid/plasm
odial
Coenocytic Rhizomorphs,
Stroma
Sclerotia)
Plectenchyma: all
organized fungal
tussue, somatic &
reproductive
Prosenchyma:
loosely woven
hyphae, parallel in
orientation
Pseudoparenchyma
: closely packed
hyphae, more or
less isodiametric

4. LOOSE -Prosenchyma
COMPACT -
Pseudoparenchyma
•Rhizomorph- root like
•Sclerotium – sherical or oval
bodies
•Pseudosclerotium – oval
bodies but center filled with
sand
•Stromata-mattress like
•Appresorium –plug like
•Hausteria – absorbative
HYPHAL
AGGREGATION
AND MYCEALIAL
MODIFICATION

5. A false tissue formed by aggregation of hyphae is
known as plectenchyma. All fungal tissues come
under this general term.
Prosenchyma.
Loosely woven tissue of
hyphae.
Pseudoparenchyma
In the fructifications of higher
fungi, the hyphae become
woven and intertwined into a
compact mass.
The hyphae- composing
it do not lose their
identity.
They run more or less
parallel to one another
and are composed of
elongated cells.
The walls of the hyphae in the
mass get fused and they lose
their individuality
, The hyphal mass appears to
be continuous structure
consisting of isodiametric or
oval cells
). It bears a striking superficial
resemblance to the parenchyma
tissue of the higher plants

6. AGGREGATION OR ADHESION OF HYPAHAE, mass
behaves as an organised unit
RHIZOMORPH – ROOT LIKE
•A thick strand or root like aggregation of somatic hyphae is called Rhizomorph. The hyphae loose
their identity and individuality and the whole mass behaves as an organised unit. It is believed that
rhizomorph has a higher infection capacity than individual hyphae Examples of Rhizomorphs are
found in Armillariella mellea.
Sclerotium (pl. Sclerotia) PERENATTING STRUCTURES GLOBOSE OR
ELONGATED
•It is formed by the aggregation and adhesion of hyphae. It may survive for long periods of time
sometimes for several years and thus represent the resting stage of the fungus. The sclerotia usually
germinate to form hyphae or may form reproductive structures. Sclerotia are commonly formed in
Claviceps purpurea, Rhizoctonia solani and Macrophomina phaseoli
Pseudosclerotium (pi. pseudosclerotia)
•These sclerotia like bodies are formed at the base of various fruit bodies of higher fungi. In
Polyporus basilapiloides, the pseudosclerotia formed below the soil surface are composed of sandPolyporus basilapiloides, the pseudosclerotia formed below the soil surface are composed of sand
particles surrounded by hyphal aggregations.
Stromata- LIKE MATRESS BEARS REPRODUCTIVE STRUCTURES
•Generally, sclerotia on germination form stromata in which reproductive structures develop.
Appressorium (pl. Appressoria ECTO PARASITIC STRUCTURES
•These are common in parasitic fungi mostly ectoparasites. An appressorium is a terminal simple or
lobed swollen structure of germtubes or infection hyphae. It adheres to the surface of the host and
helps in the penetration of hyphae of the pathogen. Appressoria are commonly formed by the
parasitic members of the order Erysiphales
Haustorium (pl. Haustoria) INTRACELLULAR ABSORBITING STRUCTURE
OF OBLIGATE PATASITES -knob shaped or branched finger shaped
•Haustoria are usually produced in those fungi in which inter­cellular mycelium are found.

8. APPRESORIA AND
AHAUSTERIA 

9. Function of cell
wall
Protects against
osmotic lysis
Acts as a
molecular sieve
wall Contains
pigments for
protection
Binding site for
enzymes

10. The cell wall is made up
of:
Primary cell wall
Chitin (polymers of
acetylated amino sugar
nacetyl-glucosamine)
Glucan(POLYMER OF BETA
 
Secondary cell wall
Chitosan
AMORPHOUS GLUCAN
13 AND 16 GLUCOSE)
AMORPHOUS GLUCAN
PIGMENTS LIKE Melanins
Lipids
Proteins AND Enzymes
include cellulase which
acts on cellulose of plants.

12. Glucan

14. Nuclear status:
Nucleus
eukaryotic; uni, bi-
(dikaryons) or
multinucleate; nucleolus
present,haploid, diploid
(less frequent), homo-
or heterokaryotic
Cell division
mitosis
intranuclear (except for
slime molds); nuclear
membrane doesn't
breakdown during
mitosis
centric
centric in flagellated
forms; typical centrioles
of euk's; paired,
cylinders of 9 triplets of
microtublues ,
associated w/nuclear
membrane
noncentric
noncentric in
nonflagellated forms;
possess spindle pole
bodies (SPBs); differ
from centrioles in
lacking microtubular
component , associated
w/nuclear membrane

15. Nutrition:
heterotrophic, absorptive,
produce extracellular
enzymes
saprobes; pathogens;
symbionts (parasites -
commensals - mutualists)
the role fungi play in their
immediate environment is
governed by what
extracellular enzymes they
can produce

16. Fungal basic mode of nutrition- are unable to
produce their own food. HETEROTROPHIC
saprophytes parasitessaprophytes
rely on dead and
decaying organic
matter for their
nutrition
parasites
completely depend
on another LIVING
organism for their
nutrition.

17. NUTRITION
SAPROPHYTES
ECTOTROPHIC ENDOTROPHIC
PARASITES
OBLIGATE PARASITES FACULTATIVE
SAPROPHYTES
FACULTATIVE
PARASITESECTOTROPHIC
GROWN ON THE
SURFACE OF DEAD
ORGANIC MATTER
ENDOTROPHIC
GROWN INSIDE OF
THE DEAD ORGANIC
MATTER
OBLIGATE PARASITES
LIVE ONLY AS
PARASITY ON LIVING
HOST
PUCCINIA GRAMINIS
TRITICI
FACULTATIVE
SAPROPHYTES
PARASITES BUT
CAPABLE OF THRIVE
IN DEAD ORGANIC
MATTER IN ABSENCE
OF LIVING HOST
TAPHRINA
FACULTATIVE
PARASITES
USUALLY
SAPROPHYTES BUT
UNDER CERTAIN
CONDITION THEY
PARASITIZE
FUSARIUN,
PYTHYIUM

18. British mycologist, GC Ainsworth (1905-1998) was former
director, Commonwealth Mycological Institute. His scheme
of classification was considered as an ideal one that reflected
natural relationships.Classification of Fungi by Ainsworth G.
C. (1966, 71, 73):. Ainsworth G. C. (1966, 71, 73) proposed a more
natural system of classification of fungi. This classification is
based on morphology, especially of reproductive structure.
He includes fungi along with slime molds under the kingdom
Mycota. G.C. Ainsworth (1971) has upgraded the fungi uptoMycota. G.C. Ainsworth (1971) has upgraded the fungi upto
kingdom level. He has treated the fungi in a separate
kingdom, or a sub-kingdom of plant kingdom..
1. Free-living, parasitic or mutualistic symbionts, devoid of chlorophyll.
2. Cell wall composition is very variable, majority contain chitin and glucan.
3. Reserve food materials are oil, mannitol and glycogen.
4. Except some unicellular members, majority are filamentous.

20. The conidial forms produce conidia on conidiophores arising directly from the somatic hyphae which may be
hyaline or bright-coloured.
The somatic hyphae may be loose; separate; innate or not
conidiophores grow for some distance above their
supporting substratum, so that the terminal parts at least
stand out at separate threads. In majority of cases the
conidia are borne exter­nally on the conodiophores
which may or may not be clustered
closely aggregated to form
sporogenous structures,
having no
specific shape
acervulus,
sporodochium
having no
specific shape
pycnidia
synnema.

21. Asexual reproductive structure
Open
condiophores
and conidia
Closed in
chamber
conidia and
conidiophores
Synnema;
this is a cluster of conidiophores
that adhere to each other along
some of their length, forming an
elongated stem or bristle-like
structure (called a fascicle, this
being Latin for ‘a
bundle’). Synnemata (that’s the
plural form) may have many
hyphal strands in their structure
and be fleshy, hard or brittle in
structure. The apical portions of
the conidiophores that make up
the synnema are separate and
radiate outward, often producing
a mucus slime in which the conidia
are trapped
Sporodocium
A compact, cushion-
like aggregation of
hyphae on which
conidiophores are
formed in a dense
layerThe aggregation
of hyphae is called a
stroma (pl. stromata)
Acervulus
Bowl shaped -It
has the form of a
small cushion at
the bottom of
which short
crowded conidioph
ores are formed
Pycnidia
flask-shaped
cavity from the
surface of the
inner walls of
which spores are
produced

23. Ascocarp types

26. Occurrence
• occurs in air, water soil and on
plants and animals
• They prefer to grow in warm and
humid places.
Thallus organization
• Unicellular-yeast,Synchytrium
• Multicellular
• Aseptate
• Septate
• Dimorphic both form unicellular
and filamentous form exist.
Candida albicans
General
characteristics
of fungi

27. Holocarpic
• the entire thallus gets converted
into one or more reproductive
bodies. Hence, the vegetative
and reproductive phase can
never occur at the same time.
Eucarpic
• Here only a part of the thallus is
involved in the development of
reproductive organs and
remaining thallus remains
vegetative. In eucarpic fungi,
vegetative and reproductive
phases exist at the same time.
Gen
characteristics
(reproduction)

28. Asexual Reproduction:
It commonly occurs through spores, either motile or non-motile and
form in a specialized part of mycelium.The various types of spores are:
ZOOSPORES,
SPORANGIOSPORES (=APLANOSPORES),
CONIDIA, OIDIA (ARTHROSPORES),
CHLAMYDOSPORES,
GEMMAE,
UREDOSPORES,

30. Sexual
on
Sexual
reproducti
on
Phases
plasmogamy
fusion),
plasmogamy
(protoplasmic
fusion),
karyogamy (fusion
of nuclei)
meiosis (reduction
division of zygote).
Planogamet
ic
copulation
Isogamy Synchtrium
Anisogamy Allomyces
Oogamy Monobleph
aris
Gametangial
contact -two
gametangia of
opposite sex come
in contact with one
another,transfers
male nucleus or
games through a
Phytophthora,
Sphaerothera,
Albugo, Pythium
Methods
games through a
pore or through
atube
Gametangial
copulation- In
involves the fusion
of entire contents
of two gametangia
to form a common
cell called zygote
or zygospore
Mucor,
Rhizopus.
Spermatizatio
n
Some fungi produce many minute, spore-like,
single-celled structures called spermatia (nonmotile
gametes). These structures are transferred through
agencies like water, wind and insects to either
special receptive hyphae or trichogyne of
ascogonium. The contents migrate into receptive
structure. Thus dikaryotic condition is established,
e.g. Puccinia.
Somatogamy
where formation of gametes is absent. Inwhere formation of gametes is absent. In
such fungi, anastomoses takes place
between hyphae and their somatic cells fuse
to produce dikaryotic cells, e.g, Agaricus

33. Shows a typical
tripartite structure
under the electron
microscope. There is
an electron dense
layer on either side
of the less dense
The characteristic marker enzyme for the plasma membranes (PM) is
a cation-dependent(h+ atpase )of mr∼100000 perform functions:
maintaining ionic and electric balance between the cell interior and
the environment; creating background conditions for water balance
(i.E. Turgor regulation in fungi,), and mediating energy transfer from
redox and dehydration
Fungal cell membranes
contain ergosterol,
whereas mammalian cell
membranes
contain cholesterol. Some
antifungal drugs bind to
ergosterol and thereby
increase plasma
membrane permeability,
whereas other drugs
Plasma membrane -delicate,
extremely thin(a 30 Å
hydrophobic film), closely covers
the protoplast. Adjoing to cell
wall except some places make
some convoluted packet enclosing
granular or vesicular
material.Moore and mc lear (1961)
named it lomasome
of the less dense
central region.
whereas other drugs
inhibit the synthesis of
ergosterol

34. Nucleus-
In the fungi nuclei are smaller sized
•1 - 3 µm, compare to other eukaryotic organisms 3 - 10 µm.
•Low – moderate chromosome number
•low (4-8), although much higher chromosome numbers may occur as well (e.g. 21 of Ustilago
maydis (corn smut)).
the amount of DNA is generally less, even allowing for the haploid state of most
nuclei.
Size of DNA varies Albugo laibachii 37 Mb, Phytophtora infestans 240 Mb
number of nuclei in single cells varies based on different fungal groups and/or life
stages.aseptate coenocytic hyphae e.g., the species of the coenocytic
Glomeromycota could have even thousands of nuclei in one asexual
chlamydospore.
Condition : in lifecycle of fungi with monokaryotic and dikaryotic hyphae -nuclei varies .
• Ascomycota of the family -order Pezizales (cup fungi) have multinuclear ascospores,
•sometimes even more than eight nuclei in one spore.
•Dikaryotic hyphae, are unique to the Ascomycota and Basidiomycota. (two groups is called
Dikarya.) The dikaryotic hyphal stage is relatively short in Ascomycota, In contrast,the
Basidiomycota is dominated by the dikaryotic phase.
Nuclei may move through the cytoplasm of most filamentous fungi, even through
the dolipore septum of the Basidiomycota
Majority of "fungi" vegetative haploids. Oomycota vegetatively diploid,Some "fungi"
alternate haploid and diploid phases
Most phycomycetes "fungi" multinucleate, whereas most "yeasts" uninucleate

35. Cell division
1. Many fungi perform special, so-called closed cell division (both meiotic and
mitotic), during which the nuclear membranes, thus the nuclei, remain intact.
These cell divisions are endonuclear, as chromosomes are segregated within
the nuclei.
2. The special organelles, the spindle pole bodies (SPB) play a crucial role in the
orientation of microtubules (MTs); in some fungi, other MT-organizing-centers
(MTOCs) also appear during cell division.
3. The kinetochore MTs connected to the SPBs segregate the chromosomes
within the nuclei, while the interpolar MTs, also connected to SPBs, help
separate the two poles of the nucleus. The astral MTs are outside the nucleus,
and connected to SPBs. The size, form and organization of the SPBs may vary
between different fungal groups.
Cell in the
A: G2-M phase
B: anaphase
C: early thelophase.
1: nuclear membrane;
2: astral microtubules (MT);
3: interpolar MT;
4: kinetochor;
5: kinetochor MT;
6: spindle pole body (SPB).

36. Cytoplasm :
The cytoplasm and most organelles and inclusions of
fungal cytoplasm are typical of eukaryotic organisms
Cytoplasm is colourless in which sap-filled vacuoles are
found.
Cytoplasm is colourless in which sap-filled vacuoles are
found.
The cytoplasmic inclusions are dead, non-functional and
unimportant for fungal survival. Cell organelles are ER,
mitochondria, ribosomes, golgi bodies and vacuoles.
Lomasomes are also present between plasma membrane
and cell wall.

37. MITOCHONDRIA:
The mitochondria of fungi are clearly recognisable. They have a double
bilayer membrane and contain complex internal membranes.
They differ from other eukaryotic organisms in that the mitochondria are
commonly elongate, oriented along the hyphal axis.
The membranes are organised as parallel lamellae usually oriented along
the long axis. This orientation is particularly common in older regions of the
hypha where vacuoles comprise a large proportion of each compartment,
and the cytoplasm is between the vacuole and the wall.
The morphology of mitochondria in yeast cells may differ. Giant, branched
mitochondria have been observed in yeasts, and intermediate forms occur in
cells transforming from yeast-like to filamentous growth.

38. Endoplasmic Reticulum:
The presence of endoplasmic
reticulum in the fungal cytoplasm
has been demonstrated by the use
of electron micro-scope. It is
loose and irregular as compared
with cells of green plants.
It is composed of a system of
membranes or microtubular
structures usually beset with small
granules which by some scientists
are likened to the ribosomes. In
multinucleate hyphae, the nuclei
may be connected by ER.
In many fungi, the endoplasmic
reticulum is highly vesicular.
Usually it is loose and more
irregular than in the cells of green
plants.

39. Golgi apparatus :
Except in Oomycetes and
non-fungal eukaryotic
cells, golgi
apparatus is rare
occurrence in fungal cells.
In Oomycetes, golgi
apparatus consists of
stacks of folded
membranes functioning in
secretion.
Major function is to
process and package
macromolecules (proteins)
and transportation of
lipids around the cell.

40. Cytoplasm inclusion
Cytoplasm consists of various inclusions such as lipid droplets and
glycogen, carbohydrate trehalose, proteinaceous material and
volutin.
The vacuoles contain glycogen.The vacuoles contain glycogen.
Several metabolites are secreted by the cytoplasm.
In matured cell, lipids and glycogen are abundantly present.

41. Septa
Depending upon the species, the protoplasm may form a continuous,
uninterrupted mass running the length of the branching hyphae, or the
protoplasm may be interrupted at intervals by cross-walls called SEPTA. Septa
divide up hyphae into individual discrete cells or interconnected HYPHAL
COMPARTMENTS.
There can be various type of septa present in different fungi. They areThere can be various type of septa present in different fungi. They are
complete septa, perforated septa, dolipore septa, etc.
septa:-Act as STRUCTURAL SUPPORTS.
It Act as the FIRST LINE OF DEFENCE when part of a hypha is damage.
It Facilitates DIFFERENTIATION in fungi.

43. Vacoules-tubules are essential
for cell function in fungi.
Vacuoles
Shape: spherical to tubular
vacuoles.
Location: longitudinally within
hyphae in the hyphae
Tubules _discovery of tubules is relatively
recent. Previously, use of chemical fixative
caused tubules to fragment into vesicles.
Use of fluorescent markers and
microscopic examination of living hyphae
have enabled the tubules to be observed
and their dynamism followed.
Location: Tubules are
most concentrated in the
Location: longitudinally within
hyphae in the hyphae
form a network within a cell
they pass through pores of the
septa,
function : store enzymes, other
macromolecules, lipids, mineral nutrients
such as polyphosphate, and toxins
recycling, storage and transport control of
pH and ion homeostasis.
Vacuoles in filamentous fungi utilise
microtubules and their motor proteins for
movement
most concentrated in the
hyphal tip
Movement: of tubules
and associated vesicles
is controlled by the
cytoskeleton

44. Thanking youThanking you