PROTISTA II
Mostly SINGLE CELLED
PHOTOSYNTHETIC AUTOTROPHIC
Eukaryotes - Algae

Secondary Endosymbiosis
Green Algae

Fig. 28.3

Cryptomonad
–Cryptomonad algae chloroplast still
–contain a vestigial nucleus called a nucleomorph
.

Tertiary Endosymbiosis ?!! Fig. 28.25
Origins of plastids,
Not phylogeny of
Cell (cytoplasm) itself.
Dinoflagellate

Dinoflagellata
• Cellulose cell walls
• Phytoplankton- base of food chain
• 2 flagella
– One in transverse grove
– One propels them along
– Spiral in water as they swim
– Cause red tides – toxic
– Bioluminescence
– zooxanthellae

Stramenophiles
Water “Molds” & Diatoms
Brown Algae

Oomycota
• Water “molds”
• Hyphae
• Diploid dominant
• Swimming zoospores
• Cellulose cell walls
• Saprobic & disease causing
– Potato blight
– Sudden Oak Death

• Attacks goldfish

Saprolegnia

Bacillariophyta
• Diatoms
• Plates of SiO
2
• Ripple membrane along plate to move ???
• Golden brown color- pigments
• Diatomaceous earth – microfossils
• Major autotroph in cold water

BACILLARIOPHYTA (DIATOMS)
• Cell wall of silica
• Cell wall consists of two valves
• Buoyancy
• Pigments
– Chlorophyll a and d
– Fucoxyanthin
– Xanthophyll, -accessory

Diatoms

Synedra sp.

Phaeophyta
• Brown Algae- the Kelps
• Can grow large !!! Fast !!
• Use Chlorophyll a & Fucoxyanthin as pigments
– Holdfast
– Stipe
– Blade
• We’ll see them at M Bay Aquarium, or
Bodega Bay

PHAEOPHYTA
• Mostly marine
• Largest Algae
• Kelp
• Pigments
– Chlorophyll a and fucoxanthin

• Blade
• Stipe
• Holdfast

Nereocystis

Fucus
Gas Bladder

Male Plant with Antheridia conceptacle

Female Plant with Oogonia conceptacle

RHODOPHYTA
• Mostly marine
• Pigments
– Chlorophyll a
– Phycobilins – phycocyanin & phycoerythrin

Rhodophyta
• Red Algae
• Carageenan
• Agar
• Use chlorophyll a & Phycoerithrin , phycocyanin as pigments

Polisiphonia n= female plant
Makes n carpospres that become 2n zygotes
2n –plant
Makes
N tetraspores n= male plant
Makes n spermatia

2n –plant Makes (n) tetraspores

female plant (n)
Makes carpospores that become 2n zygotes male plant (n) makes spermatia

Multicellularity
• Arose independently several times in
Eukarya
• Caused another new wave in evolution
• Origins in simpler colonial forms –
Volvox
• Cellular specialization and Division of labor
• Escape cell size limitations
– Membrane area to cytoplasm volume ratio

• Multicellularity solves ratio limits Fig 7.5

Viridiplantae??
Red Algae
Green Algae
Plants

Tentative
Phylogeny
Fig 28.8

CHLOROPHYTA
• Most fresh water, some marine, symbiotic with fungi in lichens.
• Chlorophyll a and b, carotenoids
• Cellulose cell walls

Chlamydomonas

Pandorina

Pandorina

Desmids

Spyrogyra

Spirogyra conjugation

Volvox

Volvox sp.

Volvox zygotes

Oedogonium sp.

Oedogonium

Euglena – example of cellular complexity in Protists

Ulva sp.

Dinoflagellates
• Two flagella one wrapped inside grove.
• Cell walls of cellulose
• Can cause red-tides – and disease for some organisms
• Similar pigments to red algae

KINGDOM PARABASALA
Phylum Euglenophyta

Euglena – example of cellular complexity in Protists

Physarum

Physarum (Life Cycle)