BIOL 226 Lecture Notes - Lecture 8: Euglenid, Diplomonad, Mixotroph
3 May 2018
School
Department
Course
Professor
Biol 226 – Ch28
Protists
What are protists?
o Mostly unicellular eukaryotes
o Some are colonial or multicellular
o Most simple eukaryotes
o But are very complex on a cellular level
o Classified life into 3 kingdoms : Plantae, Animalia, Protista
o Fossil: 1.8 BP
o Nucleus
o Membrane-enclosed organelles
o Cytoskeleton : structure of the cell and asymmetric from
Modes of nutrients
o photoautotrophs : contain chloroplasts
o Chemo heterotrophs : absorbing organic molecules or ingesting larger food particles
o Mixotrophs : combine photosynthesis and chemoheterotrophic nutrition
Primary endosymbiosis: Plastids (Chloroplast) result of an endosymbiosis of gram negative cyanobacteria
within a eukaryotic host
producing a
photosynthetic
eukaryotic cell
Secondary
endosymbiosis: plastid
acquisition events
occurred on several
different occasions via
an endosymbiosis
between red or green
algae with
nonphotosynthetic
eukaryote host ( must
have had the ability to
phagocytose whole
algal cells possessed by
ciliate
Super groups of Protists:
Excavata
1. Diplomonads
2. Parabasalids
3. Euglenozoans
o Diplomonad
Reduced mitochondria is called mitosomes
Lack functional electron transport chains so cannot use oxygen to extract
energy
o Parabasalids
Reduced mitochondria is called
The best-known paraboloid is Trichomonas vaginalis, a sexually transmitted
parasite that infects some 5 million people each year.
o Euglenozoans
o Heterotroph
o Photosynthesis
o Autotroph
o Mixotroph
o A crystalline rod of flagella
o Euglenids
A euglenid has a pocket at one end of the cell from which one or two flagella
emerge.
Many are mixotrophs: In sunlight they are autotrophic, but when sunlight is
unavailable, they can become heterotrophic, absorbing organic nutrients from
their environment. Many other euglenids engulf prey by phagocytosis
SAR clade
o Stramenopiles :photosynthatic organisms
Diatoms
Golden Algae
Brown Algae
o Alveolates : photosynthetic, pathogens (plasmodium (malaria))
Dinoflahellates
Apicomplexans
Ciliates
o Rhizarians : many species of amoebas which have pseudopodia
Forams
Cerozoans
Radiolarians
Stramenopiles:
o Photosynthetic
o Flagella has hair like projections paired with a shorter smooth flagellum
Diatom
unicellular algae
glass-like silica shell
Golden algae
The characteristic color of golden algae results from their yellow and brown carotenoids.
typically biflagellated
Brown algae
Multicellular
most are marine.
Document Summary
Modes of nutrients: photoautotrophs : contain chloroplasts, chemo heterotrophs : absorbing organic molecules or ingesting larger food particles, mixotrophs : combine photosynthesis and chemoheterotrophic nutrition. Primary endosymbiosis: plastids (chloroplast) result of an endosymbiosis of gram negative cya within a eukaryotic host producing a photosynthetic eukaryotic cell. Secondary endosymbiosis: plastid acquisition events occurred on several different occasions via an endosymbiosis between red or green algae with nonphotosynthetic eukaryote host ( must have had the ability to phagocytose whole algal cells possessed by ciliate. Lack functional electron transport chains so cannot use oxygen to extract energy: parabasalids. The best-known paraboloid is trichomonas vaginalis, a sexually transmitted parasite that infects some 5 million people each year: euglenozoans, heterotroph, photosynthesis, autotroph, mixotroph, a crystalline rod of flagella, euglenids. A euglenid has a pocket at one end of the cell from which one or two flagella emerge.
