Units 16 and 19
Units 16 and 19
 Cladistics- Emil Hans Willi Henning
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Cladograms
Shows similarities in the molecular structure of
organisms
Each node lists derived characters
Units 16 and 19
Cladistics
Classifies based on
evolutionary ancestry
Linnaean taxonomy
Classifies based on
morphological similarities
Units 16 and 19
Protists
Eukaryotes that are neither plants,
animals, or fungi
Theme for the day:
Variation
Units 16 and 19
Units 16 and 19
Protists live in almost any
environment that contains
water.
Their true phylogeny is
the subject of research
and debate
Protista
 Some
are even bioluminescent forms
 They utilize an enzyme…… luciferinase
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Dinoflagellates
Units 16 and 19
Most are microscopic, but
some are large (kelp)
Think junk drawer 
Units 16 and 19
 Complex
and diverse
 moving body parts, environments
Cilia
Flagella
Units 16 and 19
 Most
microbial eukaryotes have both
sexual and asexual reproduction.
Asexual processes:
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Binary fission —equal splitting; mitosis followed by
cytokinesis
Multiple fission —splitting into more than two cells
Budding —outgrowth of a new cell from the surface of an
old cell
Spores —specialized cells that are capable of growing
into a new individual
Units 16 and 19
 Let’s
look at some examples……………
Units 16 and 19
 1.Plant
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like Protists
Commonly called Algae
Units 16 and 19
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Many are constituents
of plankton—
free floating,
microscopic, aquatic
organisms
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Plankton that are
photosynthetic are
called phytoplankton
Units 16 and 19
 Diatoms
(a clade) are dominant in the
phytoplankton.
 They do one-fifth of the carbon fixation on
Earth.
Units 16 and 19
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Phylum Bacillariophyta
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They are among the most important aquatic micro-organisms
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Diatoms
Photosynthetic
Food source for marine organisms today
About 100,000 existent species and many thousands of extinct species
(diatomaceous earth )
Protista
 Diatoms
form glassy cell walls of silica.
These walls are exceptionally strong, and
perhaps enhanced defense against
predators.
Units 16 and 19
Phylum Chlorophyta
green algae
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A. About 17,000 species
B. This is the group which gave rise to the
true plants ****
C. Very diverse division with a wide variety of
life forms and life histories
Units 16 and 19
 Phylum Rhodophyta
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red algae
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About 4,000 - 6,000 species
 Mostly marine
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Sushi
Agar
Phycobilins
Terpeniods
Units 16 and 19
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Phylum Euglenophyta
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The outer part of the cell
consists of a firm but
flexible layer called a
pellicle
Capable of photosynthesis
Can capture food
Units 16 and 19
 2.
Fungus-like Protists
Units 16 and 19
Phylum Myxomycota
Plasmodial
slime molds
Once classified as a fungi but…….
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Movement is by cytoplasmic streaming—outer cytoplasmic
region becomes more fluid, and cytoplasm rushes in
As it moves, the plasmodium engulfs food particles by
endocytosis
sclerotium
• Plasmodium
Fan shape
Units 16 and 19
 Phylum Oomycota, Saprolengina
 genus of freshwater mold often called a
"cotton mould" because of the characteristic
white or grey fibrous patches it forms
Units 16 and 19
 3.
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Animallike Protists
1. those that move by false feet
2. those that move by flagella
3. those that move by cilia
4. those that are nonmotile
Units 16 and 19
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Phylum Euglenophyta
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parasitic flagellate
protozoa
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Trichonympha spp.
Units 16 and 19
 kissing
disease
 Trypanosoma cruzi
Units 16 and 19
 Chagas'
disease
Units 16 and 19
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Chagas' disease
 In the early, acute
stage symptoms are
mild and are usually
no more than local
swelling at the site of
infection
Units 16 and 19
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As the disease progresses,
over as much as twenty years,
the serious chronic symptoms
appear:
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heart disease
malformation of the intestines
Units 16 and 19
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If untreated, the chronic
disease is often fatal.
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Current drug treatments
for this disease are
generally unsatisfactory
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Lampit™ tablets (active
ingredient: nifurtimox)
Available drugs being
highly toxic and often
ineffective, particularly in
the chronic stage of the
disease.
Units 16 and 19
 EDUCATION