Protists Flashcards
Hypothesis for start of Eukaryotes
Ancestral Prokaryote > membrane infolding for nucleus and endomem system > swallow aerobic bacterium, become mitochondria > Eukaryote. > swallow photosynthetic bact., become plastid
Proof endosimbiosis cause mitochondria and chloroplast/plastids
Mito and plast have circular DNA, own ribosomes, enzymes and transport systems homo to bacteria, replicate similar to bacteria, double membrane.
What organims do protists include?
Most unicellular but some colonial and multicell. Simple organisms but complex cells. Some have unique organelles to Eukaryotes.
Why was Kingdom Protista abandoned?
Some protists are closer related to plants/fungi/animals than other protists.
Protists cell structure, modes of nutrition, and types of reproduction?
Complex cell structure, some have contracting vacuoles.
Phototrophs, heterotrophs, mixotrophs (mix of photo and hetero).
Asexual and sexual.
Euglebozoa: What nutritional modes to euglenids have?
Predatory heterotrophs
Photosynthetic autotrophs
Parasites
Many species are mixotrophs
Euglena distinct characteristics
Pocket at end of cell where 1 or 2 flagella emerge.
Rod in flagella.
Pellicile (protien band beneath membrane allows change of shape).
Light detector at base of flagellum
Euglena clade and clade group
Euglenozoa
Excavata
Paramecium clade and clade group
Cillates
SAR
Distinct features of Paramecium?
Cilia to move and feed.
Predatory hetorotrophs.
Oral groove for phagocytosis
Two types of nuclei (micronuclei and macronuclei)
Contractile vacuole
Pellicile (thick skin?)
Structure that lets paramecium move and feed?
Cilia, arranged in rows or tufts
Paramecium two nuclei uses?
Micro: Exchange DNA for sexual reproduction
Macro: used to make RNA and protiens.
Brown alge clade and clade group
Brown alge
SAR
Why are brown alge protists unique?
Sime of most important Photosynthetic organisms.
Most large and complex, multicellular.
Marine environments.
“Seaweeds”
Autotrophic
Color due to carotenoids in plastids.
Land plants are decended from…
Green algae
Red algae and green algae clade group
Archaeplastida
Red algae features
Most common large algae I costal waters of tropics.
Usually multicellular.
No flaggellated stages during life cycles.
Red color due to phycoerythrin that masks chrolophyll.
Lives in deeper waters than other Photosynthetic eukaryotes.
Green algae features.
Chloroplasts similar to plants.
Two main groups (Chlorophyll and Charophyceans).
Mostly in fresh water.
Unicellular, colonial, and multicellular forms.
Green alge two maim groups, which one closer to plants?
Chlorophyll and Charophyceans.
Charophyceans.
Amoeba characteristics
Lobe or tube-shaped pseudopodia.
Amoebas include free-living and parasitic species.
Most ate heterotrophs.
Use pseudopodia to feed.
Eat bacteria and protists, some eat detritus.
Slime moulds
Thought to be fungi in past.
Plasmodial and cellular slime molds.
Aggregates during food scarcity and to form fruiting bodies.
Phagocytosis food from decomposing material.
Plasmodial slime molds
Often brightly pigmented.
Giant mass with many nuclei but not multicellular.
Cytoplasmic streaming to distribute food and oxygen.
Cellular slime molds
Forms multicellular aggregates, still separated by cell membranes.
Each cell stays separate by membrane and feeds individually.
Protist role in Biosphere.
Symbiotic protists: helps termites eat wood. Helps coral
Photosynthetic: Coverts light into organic compounds. Foundation of food webs. Main producer in aquatic communities.
