Protists Flashcards
Protists
Informal name for unicellular eukaryotes; more diverse than any other group of eukaryotes
Protists being nutritionally diverse includes:
Photoautotrophs, heterotrophs, and mixotrophs
Mixotrophs
Combine photosynthesis and heterotrophic nutrition; unique to protists
What are the four super groups of protists?
Excavata, SAR, Archaeplastida, Unikonta
Amoebozoans
Part of the Unikonta super group; includes amebae and slime molds
Amebae
Have pseudopodia instead of cilia or flagella, grows by cytoplasmic steaming (cytoplasms undergoes reversible phase change from solution to gel), has food vacuoles, contractile vacuoles for water and wastes, generally complex internal structure; part of the Amoebozoans
Pseudopodia
Extensions of cytoplasms shaped by micro tubules and micro filaments; “fake feet or legs”
Slime molds
Once thought to be fungi because they produce fruiting bodies and spores, but just convergent evolution; two types: plasmodial slime molds and cellular slime molds; part of the Amoebozoans
Euglenozoans
Characterized by rod w/ spiral or crystalline structure inside each of their flagella; has two types: kinetoplastids and euglenids; part of the Excavata super group
Kinetoplastids
Some are free living (facultative) or parasitic (obligate); causes diseases like African trypanosomiasis, Chagas’ disease, Leishmaniasis
Why trypanosome diseases cannot be treated w/ antibiotics?
Both host and parasite are eukaryotes, so anti-protozoan drugs are harmful
Red and green algae
Part of the Archaeplastida super group; closest relative to land plants and developed from cyanobacterial endosymbionts
Radiolarians, forams, Cercozoans
Move and feed w/ pseudopodia; part of the Rhizarians sub category; part of the SAR super group
Ciliates
Are alveolates; cilia usually occur in large numbers, ciliary beating is coordinated (metachronal/moving together); part of Chromalveolata sub category; part of the SAR super group
Difference between ciliates and free moving ciliates
On free moving ciliates, direction of swimming is opposite the direction of power strokes
Apicomplexans
All parasites of animals and have apex organelles that penetrate and infect the host, has a long and shared evolutionary history, must infect a series of hosts and change between sexual and asexual phases throughout its life cycle; are alveolates; part of the Chromalveolata sub category, part of the SAR super group
Sporozite
Infective stage caused by apex organelles of the apicomplexans
Plasmodium
Causes malaria; an apicomplexan
Merozite
Infected red blood cell
You find an organism that has apex organelles, and is a parasite. What class does it most likely belong to?
SAR (specifically Apicomplexans)
While studying a sample under a microscope you notice an organism that uses a food vacuole and a contractile vacuole. What class does it belong to and what is the purpose of the food vacuole and contractile vacuole?
Unikonta (Amoebozoans)
While looking at a droplet of water through your microscope you find an organism that is able to easily swim through liquids but pushing water in the opposite direction it wants to go through use of a flagella. What class does this organism most likely belong to?
Excavata
According to the phylogeny presented in this chapter, which protists are in the same eukaryotic super group as plants?
Red and green algae
