Protist, Fungi,
Bacteria and
Lichens
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Are prokaryotes, do not have a nucleus
Do not have complex chromosomes
Do not reproduce sexually
Unicellular
Lack cell organelles except ribosomes
Can be autotrophs or heterotrophs
 Cells have diversity of shapes, the most
common being:
1. Spherical: coccus
2. Rod: bacillus
3. Spiral: spirillium
 Grouping of cells includes:
1. Staphylo: clustered
2. Strepto: chain
 Diameter of cells 1-10 micrometers,
eukaryotes 10-100 micrometers
bacillus
Coccus
Spirillium
Strepto
Staphlo
Prokaryotes external cell walls maintain
the cell shape, protect the cell and are
composed of peptidoglycan (a modified
sugar cross-linked by short
(polypeptides.)
The peptidoglycan cell wall
composition can be used to identify cells
thru a staining process called gram stain
 A stain used to distinguish 2 groups of
bacteria by virtue of a structural difference
in their cell wall:
1. Gram positive:
• Have large amounts of peptidoglycan in cell
wall and stain blue
2. Gram negative:
• Have small amounts of peptidoglycan, stain
pink, and are more often disease-causing
than gram positive.
• Gram negative
bacteria
• Gram positive
bacteria
 Motile bacteria use one of 3
mechanisms to move:
1. Gliding along secreted slime
2. Axial filaments of spirochetes allow
rotation and motion like a corkscrew
3. Flagella
Bacteria’s “Tail” (Flagella)
Bacteria’s “Tail” (Flagella)
Only an
awesome
intelligence
could create
such
irreducible
complexity.
www.soulcare.org
Sid Galloway
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1.
Neither mitosis nor meiosis occurs
DNA synthesis is almost continuous
Cells divide by:
Binary fission ( divide and produce 2
identical cells)
2. Conjugation: exchange of genetic
material
3. Spore formation: when growth
conditions become unfavorable, many
bacteria form spores
1. Photoautotrophs: use light to
synthesize orgnaic compounds. Ex
cyanobacteria
2. Photoheterotrophs: need organic
corabon but use light to make ATP
3. Chemoautotrophs: need only carbon
dioxide to make their food
4. Chemohetrotrophs: need organic
molecules for energy and as a source
of carbon. Most bacteria fit here.
 Chemohetrotrophs can be broken
down into 2 subgroups:
1. Saprophytes decomposers that
absorb nutrients from dead organic
matter.
2. Parasites: bacteria that absorb
nutrients from body fluids of living
hosts.
1. Obligate aerobe: bacteria that need
oxygen for cellular respiration
2. Facultative anaerobe: use oxygen
when present, but in its absence , it can
grow using fermentation. Ex giardia
3. Obligate anaerobe” those that are
poisoned by oxygen. Ex Clostridium
botulinium ( food poisoning)
1. Archaebacteria: live in extremely
harsh conditions, divided into 3 main
groups:
a) Methanogens: strict anaerobes, found
in marshes and swamps
b) Extreme halophiles: live in water with
extreme salinity (15 to 20 %), and form
pink colored colonies on agar
c) Thermoacidophiles: live in habitats of
60-80C and pH 2-4
2. Eubacteria: true bacteria, capable of
causing disease (pathogenic)
3. Cyanobacteria: blue-green algae, are
larger than most prokaryotes, are
photosynthetic
4. Prochorobacteria: new group of
bacteria, only 2 species known
Nostoc
Oscillatoria
. Any close
relationship between
species is called
symbiosis.
1.Mutualism
2.Commensalism
3.Parasitism
Mutualism – A symbiotic
relationship in which both
species benefit.
Parasitism – A symbiotic
relationship in which one
organism benefits but the
other is harmed.
Commensalism – A symbiotic
relationship in which one organism
benefits and the other is not
affected.
1/2 human diseases are caused
by bacteria
Some pathogens are
opportunistic…normally in the
body but become pathogenic only
when defenses are weakened. Ex
Streptococcus pnemonia
Koch’s Postulate ( Robert Koch)
• 4 criteria to substain a specific
pathogen as a cause of disease:
1. Find pathogen in all diseased
individuals
2. Isolate diseased pathogen and grow in
culture
3. Use culture to introduce disease in a
test subject
4. Isolate same pathogen in test subject
Kingdom:
Protista
• Almost all have flagella or cilia at some
time in life cycle
• All can reproduce asexually, some can
reproduce sexually
• Can be group as animal-like protist or
algae-like protist
• Are unicellular eukaryotic organisms
• May be heterotrophic or autotrophic
• Are found almost anywhere there is
water
• Can be either free-living or symbiotic
• Almost all are aerobic, using
mitochondria for cell respiration
1.
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2.
3.
4.
5.
6.
Rhizopoda: also called sarcodina
Includes amoebas and their relatives
Actinopoda: includes radiolarians
Foraminifera: marine organisms
Apicomplexa: sporozoa
Zoomastigina: flagellata
Cilophora: paramecium
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Rhizopoda: also called sarcodina
Includes amoebas and their relatives
Simplest of protist
All are unicellular
Motility via pseudopodia
Inhabit fresh water, soil and marine
Most are free-living, but some are
parasitic ex amoebic dysentary
Amoeba
• Kingdom: Protista
Phylum Sarcodina
Amoeba
• Moving amoeba
• Includes radiolarians,
• primarily marine and have delicate
shells, composed of silica
Radiolarian
• Kingdom: Protista
Phylum Actinopoda
• Exclusively marine
• Have porous, multichambered, calcium
carbonate shells
• Nonmotile
• Reproduce by means of spores
• Ex plasmodium which causes malaria
Malaria Cycle – Plasmodium
carried by Anopheles mosquitoes
• Heterotrophs that absorb organic
molecules or phagocytizes prey
• Can reproduce asexually
• Ex trypanosoma which causes african
sleeping sickness thru the bite of the tse
tse fly
Trypanosoma
• Kingdom: Protista Phylum Flagellata
PHYLUM ZOOMASTIGINA
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1.
Ex paramecium
Largest group
Have 2 types of nuclei:
Macronucleus: large, around 50 copies
of genome
2. Micronucleus: function in conjugation
Paramecium
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Paramecium
Algae-like
protist
Are aquatic organisms having
chlorophyll a and accessory
pigments such as carotenoids
Spirogyra
• Kingdom: Protista
1. Dinoflagellata: such as
Pyrrophyta
• Pyrrophyta means
Fire Protist
• cause red tides
2. Chrysophyta
• Green Golden Protist
Example:
Hydrodictyon
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• 3 kinds:
• 1. diatoms
• 2. yellow gre3n
algae
• 3. brown algae
3.Phaeophyta
• Brown Protist
• Largest most
complex protist
4. Rhodophyta
5. Euglenophyta: ex
euglena
• Kingdom: Protista
Phylum Euglenophyta
Euglena
Green protist
Examples include volvox and
Chlamydomonas
Volvox
• Kingdom: Protista
Phylum: Chlorophyta
Chlamydomonas
• Kingdom: Protista
• Phylum: Chlorophyta
Protist that resemle fungi
1. Myxomycota: ex plasmodial slime
mold
2. Acrosiomycota: cellular slime molds
3. Oomycota: watermold, white rust,
mildew
Eukaryotes, multicellular ( except yeast
which is unicellular), heterotrophs via
saprophytic activity
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Fungi are hetrotrophs that acquire
nutrients by absorption in 3 main ways:
1. Saprophytes: absorb nutrients from dead
organic material
2. Parasitic fungi: absorb nutrients form body
fluids of living host. Some are pathogenic
3. Mutualistic fungi: absorbs nutrients from a
host but reciprocate to benefit host
• Hyphae: filaments forming fungal body.
• The network of hyphae is known collectively as a
mycelium
• Cell wall composed of chitin
• Fungi are nonmotile and have no flagellated
stages in their life cycle.
• Spores are produced asexually when
conditions are habitable, and
sexually when stressed
• Sexual reproduction often involves
conjugation in which hyphae of
opposite mating stains join.
1. Zygomycetes: most primitive fungi and
reproduce sexually, most are terrestrial
fungi in soil and decaying organic
material. Ex bread mold
 Most primitive fungus to reproduce
sexually
Zygomycetes
2. Ascomycetes: includes unicellular
yeast and complex multicellular cup
fungi
• Includes decomposers and mutualistic
and parasitic symbionts
• Many live symbiotically with algae as
lichen
Ascomycete
3. Basidiomycetes: ex mushroom
• Characterized by sexual
reproduction
Basidiomycete
DON’T ever eat the ones in your yard!
Never eat hallucinogenic mushrooms,
Like “Psilocybin”.
Reality is bad enough in this fallen
world.
Why
make
it
worse.
www.soulcare.org
Sid Galloway
4. Deuteromycetes: Fungi imperfect
 Reproduce asexually ( no
observable sex life)
 Ex penicillium
Deuteromycetes
• Penicillium sp.,
Lichens
Why did the algae and the fungus
get together…..they took a lichen
to each other
• Lichens grow everywhere except where
pollution occurs.
• Are good indicators of air pollution
especially sulfur dioxide
• 2 theories as to the role of fungi:
1. They benefit algae
2. Controlled parasitism: fungi kills some
algae but not as fast as algae
replenishes itself
Crustose Lichen:
crustlike
Foliose Lichen: leaf like
Fruiticose Lichen: shrub like
Mycorrhizae
• Are specific, mutualistic associations of
plant roots and fungi
• Are seen in 90% of trees and majority of
small vascular plants
• Necessary for optimal plant growth
Pathogenic Fungi
• RINGWORMs
•
• athletes foot
Virus
• Depending on one's view point, viruses may
be regarded as aggregates of complex
nonliving chemical, or very simple living
microbes.
• Viruses are not placed in any kingdom.
• They are not composed of cells and are
incapable of growth without a host cell.
• Viruses vary in size and shape ( smallest virus
is about .002 um — polio virus and largest is
,3um — smallpox virus)
• There are no technical names for viruses.
• Viruses are classified based on types of
nucleic acid, morphological class, size of
capsid, and number of capsomeres.
• Other considerations include: virus's
susceptibility to microbial control agents, and
immunological properties
• The virus particle is known as a virion.
• The nucleic acid portion of the virus is
known as the genome, which is
surrounded by a protein coat known as
a capsid, which is formed from a
number of individual protein molecules
called capsomeres,'
• The combination of the genome and
capsid is called the viral nucleocansid.
• Some kinds of viruses contain
envelopes (enclosed nucleocapsids)( ex
herpes,chickenpox, infectious
mononucleosis) and some have
projections from the envelope
known as spikes, which help the virus
attach to the hose cell, ExAIDs
• Antibiotics cannot be used to inactivate
viruses because viruses do not perform
the biochemical functions that
antibiotics interfere with.
• However some drugs can interfere with
viral replication (virus induces
the living host cell to synthesize the
essential components for the synthesis of
new viral particles).
•
• Diagram of Virus
Rabies
AIDS Virus
Influenza Virus
Ebola Virus