Flashcards in Lecture 24 - Protists I (SI) Deck (20)
-characterized by cytoskeleton
-some have excavated feeding groove
What are the 3 groups of Excavata?
Diplomonads: reduced mitochondria (mitozones) + 2 nuclei + multiple flagella
Parabasalids: reduced mitochondria (hydrogenozomes)
Euglenozoans: spiral/crystalline rod inside flagellum
Diplomonads: anaerobic biochemical pathways
Parabasalids: generate some energy (anaerobically)
Euglenozoans: everything (hetero/auto/mixotrophs, parasites)
Diplomonads: Giardia intestinalis
Parabasalids: Trichomonas vaginalis (yeast infections)
Euglenozoans: African sleeping sickness, Euglenids
Which Excavata lack mitochondria?
What is the archaezoa hypothesis?
-protists are derived from ancient eukaryotic lineages before the cquisition of endosymbiotic bacteria that evolved into mitochondria
What is the accepted theory about mitochondria in protists?
protists lost their normal mitochondria during their evolution
-supported by molecular evidence
-members have alveoli
What are alveolli?
-small membrane-bound cavities with unknown function
-may aid in cell surface/water/ion regulation
characterized by an anterior pocket from which one or two flagella emerge
have single large mitochondrion associated with a unique organelle (kinetoplast)
What are 3 groups in chromalvealata?
Dinoflagellates: cellular plats, 2 spinning flagella in perpendicular grooves, bioluminsecent
Dinoflagellates: part of plankton or hetertrophic
Apicomplexans: anaerobic biochemical pathways
Dinoflagellates: unicellular or colonial
What is plasmodium?
-spends life cycle in mosquitoes + humans
Why has there been a resurgence of malaria?
-resistant varieties of the mosquitoes + plasmodium species
-300 million infected in the tropics
-vaccine development difficult
Why is vaccine development difficult for malaria?
parasite changes its surface proteins