Download Protista and fungi (2008

Kingdom Protista
Chapter 21
What are Protists?

Protists are eukaryotes
that are not members of
the Kingdoms: Plantae,
Animalia, or Fungi

Protists are generally
unicellular
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Protists can be
heterotrophs, autotrophs,
or decomposers
Classification
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Protists are a very diverse groups of organisms
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Different groups of Protists evolved independently
from archaebacteria
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Protists are generally classified by the way they
obtain food. There are three main categories of
Protists
Animal-like (Protozoa)
 Plant-like (Algae)
 Fungus-like

Animal-Like Protists (Protozoans)

Classified by their method of movement.
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There are four phyla of Protozoans
 Zooflagellates
 Sarcodines
 Ciliates
 Sporozoans
Zooflagellates

Animal-like Protists

Use Flagella to move
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Absorb food through
their cell membrane

Live in lakes,
streams, and inside
other organisms

Form the basis of many food chains

Asexual reproduction by means of binary
fission

Ex. Giardia- water borne protozoa that
causes severe intestinal distress
 Trichonympha –helps termites digest
wood
Sarcodines
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Animal-like
Use pseudopods for feeding and
movement
Asexual reproduction by means
of binary fission
Ex. Amoeba
Ciliates
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Use Cilia for feeding
and movement
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Cilia- short hairlike
projections

Found in lakes, streams,
and oceans
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Use self-defense mechanisms known as a
trichocyst
Reproduce by binary fission and
conjugation
Ex. Paramecium
Sporozoans

Do not move on their own

Considered parasites

Complex life cycle, involve
more than one host

Reproduce by sporozoites
 Attach to host, penetrate it,
and live within it

Ex. Pneumocystis carinii. –
causes pneumonia in AIDS
patients
 Plasmodium vivax – causes
malaria
Diseases

Some animal-like protists cause serious diseases,
including malaria and African sleeping disease

Malaria

300-500 million people suffer from Malaria

2 million die each year
Plasmodium causes malaria
Female Anopheles Mosquito is the carrier


Malaria Life-cycle
Other Diseases

Toxoplasmosis [Toxoplasma gondii]
- Caused by eating raw meat
- May become infected through the
handling of cat litter boxes
- Symptoms are similar to the flu.
- Especially hazardous to pregnant
women, may cause eye damage in
the fetus
More Diseases

African Sleeping sickness
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Fatal
Caused by the bite of a
tsetse fly
Amebic Dysentery

Causes severe diarrhea
Plantlike Protists

Contains green pigment chlorophyll

Carries out photosynthesis

Highly mobile
Euglenophytes

Plantlike

Two flagella
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Has eyespot
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Helps find
sunlight
No Cell Wall, but
has a pellicle
Ex. - Euglena
eyespot
Dinoflagellates
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Can be both
heterotroph and
autotrophs, some are
both at the same time

Two flagella –
causes to move in a
spiral motion

Asexual
reproductions by
binary fission
Red Algae

Able to live at great
depth due to their
efficiency in harvesting
light energy

Contain Chlorophyll a
and phycobilins ( absorb
blue light)

Multicelluar
Lack flagella

Brown Algae

Contains Chlorophyll a and
c as well as fucoxanthin

Largest and most complex

Multicellular

Mostly found in shallow
coastal water

Ex. - Kelp
Green Algae

Have chlorophyll a
and b
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Store food in the
forms of starch

Very similar to plants

Contain cellulose in
their cell wall
Human Uses of Algae

-Often rich in vitamin C and iron

Medicine
-treat stomach ulcers, arthritis, and high blood pressure
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Food
-ice cream, salad dressing, pudding, candy bars, pancake
syrups, and eggnog
Industry
-chemicals from algae are used to make plastics, waxes,
transistors, deodorants, paints, lubricants, and even
artificial wood
Science laboratories
-Remember Agar!!!
Fungus-like Protist

Like fungi, fungus-like protist are
heterotrophs that absorb nutrients from
dead or decaying organic matter
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Unlike fungi, fungus-like protist have
centrioles
Slime Molds
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Recycle organic
matter

Closely resemble
amoebas

Multi-cellular
Fungi
- Chapter 21
The Kingdom Fungi
•Fungi are eukaryotic heterotrophs that have
cell walls.
•These cell walls are made of chitin
The bodies of multicellular fungi are composed
of many filaments called hyphae
Fungi Reproduction
• Most fungi reproduce both asexually
and sexually
– The cells or hyphae may break off
and begin to grow on their own.
– Some fungi produce spores. This is a
form of asexual reproduction.
Spores are Asexual
Fungi Classification
• Over 100,000 species.
• Grouped according to their structure
and method of reproduction.
• Four main groups:
– Molds, Sac Fungi, Club Fungi and
Imperfect Fungi
Molds - Phylum Zygomycota
• Has both a sexual and asexual phase in
its life cycle
• Produces spores on structure called
sporangia
• Example: Bread Mold
Bread Mold
Sac Fungi
• Phylum Ascomycota
– Both a sexual and asexual phase in it’s life
cycle
– Produces spores on structure called asci
which form on the inside of the cup
– Examples:
• Yeast
• Morels
Yeast
Morels
Morels
Club Fungi
• Phylum Basidiomycota
– Both a sexual and asexual phase in its life
cycle
– Produces spores on structures called
basidia
– Basidia are found on the gills that grow on
the underside of a mushroom cap
Club Fungi (con’t.)
– Includes many edible and poisonous
varieties
– Examples: Button, Portobello and Shitaki
mushrooms
Club Fungi
The Imperfect Fungi
•Phylum Deuteromycota
–No sexual phase of their life cycle has been
observed.
–Example:
•Penicillin
Penicillin
Ecology of Fungi
• Fungi are found in all ecosystems in all
environments on Earth
• All fungi are heterotrophs
– They cannot move to capture food, but
their mycelia grow into the tissues and
cells of organisms.
– Many are saprobes, which obtain food
from decaying organic matter
– Some are parasites
– Some are symbionts
Fungi as Decomposers
• Fungi recycle nutrients by breaking down the
bodies and wastes of other organisms.
• Without fungi and other decomposers,
energy-rich compounds would forever be
trapped in the bodies of dead organisms.
• If these materials were not returned, the soil
would quickly be depleted, and Earth would
become lifeless.
Fungi as Parasites
• Some fungi cause tremendous losses of
food and crops.
• A few fungi cause human disease.
– Example: ringworm, athletes foot fungus,
yeast infections.
Ringworm
Athletes Foot Fungus
Symbiotic Relationships
• Some fungi form symbiotic relationships
in which both partners benefit.
• Lichen: An association between a fungus
and a photosynthetic bacteria or algae.
– Lichens are often pioneer species
Lichens
• Mycorrhizae: a mutualistic relationship
between a fungus and a plant. The
fungus supplies the plant with water
and minerals. The plant supplies the
fungus with sugars from
photosynthesis
Micorrhizae