Download - Plant-Like Protists (Algae)
Plant-Like Protists (Algae)Autotrophs – photosynthetic, have chloroplasts, all
have chlorophyll aClassified by pigment types / color group, food
storage, cell wall composition (7 phyla)Produce most O2 on earthNo roots, stems, leaves – make gametes in single-
celled gametangiaMost aquatic, have flagella at some stage of life cycleStore starch in pyrenoidsUnicellular (eg. Phytoplankton), multicellular (eg.
seaweeds) or colonial
Plant-Like ProtistsPhylum Chlorophyta – Green AlgaeLike plants, have chlorophyll a and b,
carotenoids, food stored as starch, cellulose in cell walls common ancestor or plants evolved from green algae
Most aquatic, some terrestrial (moist soil, tree trunks – Protococcus)
some symbiotic with invertebrates (corals) or fungi (lichens)
Some motile, some sessile
Symbiosis w/ Fungi:
LichensCrustose &
Foliose
Symbiosis with Cnidarians
Some anemones, corals, and jellyfish have symbiotic algae
(zooxanthelae)
Unicellular
Colonial
Multicellular / Filamentous
What type of life cycle is this?What is the only step that uses meiosis?
Plant-Like Protists Phylum Phaeophyta – Brown Algae
MulticellularChlorophyll a and b,
plus fucoxanthin brown accessory pigment
Most marine, include seaweeds and kelpSargassum – floating
seaweedMycrocystis pyrifera
– giant kelpsessile
Giant kelp
Kelp
Plant-Like ProtistsPhylum Rhodophyta – Red AlgaeChlorophyll a and phycobilins – red accessory
pigments that absorb light deep in water can live in deeper water than other algae
Most are marine seaweeds, sessile
Plant-Like ProtistsPhylum Bacillariophyta - Diatoms
UnicellularCell walls = shells of silicon dioxide two halves that fit
like a pill box found in beach sand, used in toothpaste, etc.Centric – round or triangular, mostly marinePennate – rectangular, mostly freshwater
Abundant in phytoplankton
Plant-Like ProtistsPhylum Dinoflagellata - DinoflagellatesUsually unicellular, have two flagella perpendicular to each
otherCell walls made of cellulose plates that resemble armour –
ex.: CerratiumMost yellow to brown – carotenoids plus chlorophyll a and cA few colorless heterotrophsSome bioluminesce – genus NoctilucaSome produce toxins & red pigment “red tides”
Ceratium
Dinoflagellate “armour”
Red tide
Bioluminescence
Plant-Like ProtistsPhylum Chrysophyta – Golden Algae
Unicellular, chlorophyll a and b, yellow due to carotenoids
Two flagella on opposite ends of cellMost live in freshwater Form highly resistant cysts survive in frozen or dry
lakesStore energy as oils formation of petroleum new
biofuels?
Plant-Like ProtistsPhylum Euglenophyta - Euglenoids
Unicellular, plant-like and animal-like:No cell walls, have protein
pellicleChloroplasts (if raised in
presence of light) Eyespot sensitive to lightContractile vacuole
Chlorophylls a and b, carotenoids
Most live in freshwater, some in moist soil and animal digestive tracts