morphology of bacteria and fungi in detail with diagrams

1. MORPHOLOGY OF
BACTERIA AND FUNGI
PRESENTED BY
MEGHA T P
MSC FOOD AND
NUTRITION
SECOND SEMESTER

2. MORPHOLOGY OF BACTERIA
INTRODUCTION
Bacteria are prokaryotic organisms.
Unicellular, free-living, microscopic microorganisms.
They posses both DNA & RNA.
Occur in water, soil, air, food and all natural environment.
Can survive extremes of temperature, pH, oxygen and
atmospheric pressure.

3. Size of bacteria
Very small organisms which can visible under microscope.
Having size range in micrones.
Stained and then visualised under high power of
magnification (1000X) of compound microscope.
Electron microscope used for clear visualization of internal
structure of bacteria.

4. Structure of bacteria

5. 1.flagella
Long, slender, thin hair-like cytoplasmic appendages
responsible for the motility of bacteria.
Organs of locomotion.
Diameter - 0.01 to 0.02 µm.
Length - 3 to 20 µm.
Made up of protein – flagellin.
Three parts
1.Filament
2.Hook
3.Basal body

6. Flagella arrangement in bacterial body
1.Monotrichous
Have single polar flagellum
Eg: vibrio cholera
2.Lophotrichous
2 or more flagella only at one end.
Eg: pseudomonas fluorescence
3.Amphitrichous
Single polar flagella at both poles.
Eg: Aquaspirillum serpens
4.Peritrichous
Several flagella present all over the surface.
Eg: E.coli, Salmonella typhi

7. 2.Pili/Fimbriae
Hair like micro fibrils.
Length -0.5 to 2µm.
Diameter – 5 to 7nm.
Thinner, shorter and numerous than flagella.
Composed of protein – pillin.
Present only in gram negative cells.
Function – pili play important role in attachment to surface.
Hence it is also called organ of adhesion.

8. 3.Plasma membrane
It separate cell wall and cytoplasm.
Composed of phospholipids and proteins.
Prokaryotic plasma membranes are less rigid compared to
eukaryotic due to lack of sterols.
Functions
Provide mechanical strength to bacterial cell.
Helps in DNA replication.
It contain enzyme permease, which helps In passage of
selective nutrients through the membrane.

9. 4.cytoplasm
Bacteria cytoplasm is a suspension of organic, inorganic
solutes in a viscous water solution.
Contain ribosomes, proteins, reserve materials and other
other water soluble components.
In most bacteria extrasomal (plasmid) DNA is also present.
5.Capsule
Bacteria synthesis loose amorphous organic exopolymer
which is deposited outside and tightly to cell wall called
capsule.

10. Composed of complex polypeptides or polysaccharides.
Water is the major component (98%).
Capsulated bacteria produce smooth and non-capsulated
produce rough colonies on surface of agar media.
Function
Protect bacteria from drying.
Protect bacterial cell aginst anti-bacterial agents and
phages.

11. 6. Cell wall
Rigid structure, which give shape to the cell.
Situated between capsule and cytoplasmic membrane.
thickness - 10 to 20nm
Cell wall of bacteria contains diaminopimelic acid(DAP),
muramic acid and teichoic acid.
These structures joined together to form complex
polymeric structure known as peptidoglycan or murein or
mucopeptide.
Peptydoglycan is major constituent of cell wall of gram
positive bacteria (50 – 90%).

12. Shape of bacteria
On the basis of shape bacteria are classified into,
Cocci – spherical
Bacilli – Rod shaped
Vibrio – Comma shaped
Spirilla – spiral shaped

13. 1.COCCI
Cocci are small, spherical or oval shaped.
According to arrangement of cells, cocci are divided into
various subtypes.
1.Monococcus
Exist as single spherical cell.
Example: micrococcus flavus
2.Diplococcus
Two bacterial cell occur as pairs.
Example: Streptococcus pneumoniae, Neisseria spp

14. 3. Tetrad
Arranged in a group of four cells that remain attached and
grow in the attachment after cell division.
Example: micrococcus spp, pediococcus spp
4.Sarcina
Occur as a group of 8 cells.
Anaerobic gram-positive bacteria.
Example: sarcina aurantiaca, sarcina lutea

15. 5.Streptococci
Arranged in long chains.
Example: streptococcus mutans
6.Staphylococcus
Arranged in grape like clusters.
Example: staphylococcus haemolyticus,
staphylococcus aureus

16. 2.BACILLI
They are rod shaped cells.
In some bacilli length of cell may be equal to width. such
bacilli known as coccobacilli.
Example: bacillus anthrasis, bacillus coagulance
ARRANGEMENT OF BACILLI
1.Diplobacilli
Occurs in pairs after division
Example: moraxella bovis, coxiella burnetii

17. 2.Streptobacilli
Bacilli arranged in chains, as the cell divide in one plane.
Example: streptobacillus moniliformis
3. Coccobacilli
Short and appear as ovoid.
They look like bacillus and coccus.
Example: haemophilus influenzae

18. 4.Palisades
The bacilli bend at the point of division following the cell
division, resulting in a palisade arrangement.
Angular patterns that looks like chinese letters.
Example: cornybacterium diphtheriae

19. 3.VIBRIO
They are comma shaped curved rods.
Example: vibrio parahaemolyticans,
vibrio vulnificus
4. SPIRILLA
They are longer rigid rods with several curves or coils.
They have a helical shape and rigid body.
Example: spirillum ruprem

20. MORPHOLOGY OF FUNGI
INTRODUCTION
Fungi are eukaryotic protista.
Unicellular (yeast) or multicellular.
Most fungi are obligate facultative aeorobs.
Cell wall containing chitin, mannan and other
polysaccharides.
Cytoplasmic membrane contains ergosterols.

21. Cytoplasmic contents include mitochondria and endoplasmic
reticulum.
The study of fungi is called mycology.
The toxins produced by fungi- mycotoxins.

22. STRUCTURE OF FUNGI
Each cell has a cell wall made of chitin.
Structure consist of
Mycelium ( mass of hyphae)
Fruiting body (reproductive structure)

23. The vegetative body of fungus is called thallus.
The plasmalemma covers cytoplasm and all cell organelles.
Nucleus is usually small.
Mitochondria , endoplasmic reticulum and vacuoles are present.
Fungi contain filamets called hyphae.
The hyphae have internal cross walls called septum.
Fungi may be septate (with septum) or aseptate(without
septum).
The septa of many species have pores, allowing cytoplasm to
flow freely from one cell to the next.
The hyphae may be branched.

24. ( Aseptate )

25. Mass of hyphae that is not a reproductive structure is called
mycelium.
Vegetative mycelium:
hyphae that penetrates the supporting medium and
absorb nutrients.
Aerial mycelium:
hyphae that project above the medium and produce
reproductive structures called conidia.

26. MORPHOLOGICAL CLASSIFICATION OF
FUNGI
YEAST
YEAST-LIKE
MOLDS/FILAMENTOUS FUNGI
DIMORPHIC FUNGI
YEAST
These occurs in round or oval bodies, which reproduce by an
asexual process called budding.
Yeast colonies resembles bacterial colonies in appearance and in
consistancy.
Example: saccharomyces cervisiae

27. YEAST-LIKE
Grow partially as yeast and partly as elongated cells resembling
hyphae.
The later form a pseudomycelium.
Example: candida albicans
MOLDS/FILAMENTOUS FUNGI
The basic morphological elements of filamentous fungi are long
branching filaments or hyphae.
Colonies are strongly adherent to medium.
Surface of these colonies may be velvety, powdery or may show a
cottony aerial mycelium.
Example: Apergillus, penicillium

28. DIMORPHIC FUNGI
These fungi exhibit a yeast form in the host tissue and in vitro at
37ºC on enriched media and mycelial form in vitro at 25ºC.
Example: Histoplasma capsulatum

29. REFERENCE
https://courseware.cutm.ac.in/wp-
content/uploads/2020/06/morphologyofbacteria-
171125164257.pdf
https://microbenotes.com/bacterial-sizes-shapes-arrangement/
https://www.researchgate.net/publication/315803754_MORPHOL
OGY_AND_CLASSIFICATION_OF_BACTERIA
https://ucmp.berkeley.edu/fungi/fungimm.html
Introductory microbiology-J.Heritage, E.G.V.Evans and
R.A.Killington