Biology 4B Laboratory
Protist Diversity
Objectives
 Learn the basic characteristics that define organisms classified within the Protist taxon
 To learn the anatomy, life cycles and identification of representative organisms from the principle
Protist phyla
 To demonstrate an understanding of the ecological and economic importance of organisms within this
taxon
Introduction
Within the Domain Eukarya, presently, there are four “super groups” which recognizes 23 kingdoms (Figure 1).
Three of these Kingdoms: Fungi, Animalia and Plantae are all the only ones still recognized from Whittaker’s
original five kingdom classification. The twenty remaining protist kingdoms comprise a polyphyletic group
historically referred to as Protista. Most of the members are single-celled organisms (originally called the
protozoa), but also included are colonial species and true multi-cellular algae (these used to be included among
the plants). Protists are also diverse in that they can have fungal-like, plant-like, animal-like or can be mixotrophic
(combination of the three). Many possess cilia, flagellum(a) or pseudopodia for locomotion. They have a
worldwide distribution in aquatic (freshwater or marine) or terrestrial environments. Protists can be aerobic or
anaerobic in their respective environments.
For lab, you are responsible for knowing the four supergroups: 1) Excavata in its members possess a cytoskeleton,
an “excavated” feeding groove or are amitochondriate, 2) SAR clade (Stramenopiles, Alveolates and Rhizarians):
Members in this supergroup have unique DNA sequences, secondary endosymbiosis with red algae, unique rRNA.
In addition some members may have: alveoli, hairy flagella and are ameboid. 3) Archaeplastida include red and
green alga groups along with land plants. Members have plastids with two membranes and are photosynthetic. 4)
Unikonta includes members that possess a single flagellum or are ambeoid without a flagellum.
Supergroup Excavata
Diplomonads
Parabasalids
Euglenozoan = Observe live and prepared slides
 Euglena = mixotrophic single celled aquatic (freshwater and marine) organism
o Observe a live specimen for euglenoid movement
o Look for the nucleus, flagellum and eyespot
 Trypanosoma spp = heterotropic single celled parasite
o Observes prepared slide, look for this flagellated organism among the blood cells
 Find the large mitochondrion
 Diseases caused:
 Africa  African sleeping sickness (vector = tsetse fly)
 Americas  Chaga’s disease (assassin or kissing bug)
Supergroup SAR Clade (Stramepiles, Alveolates and Rhizarians)
Stramenopiles = diatoms, golden and brown algae
 Diatoms = comprise another important part of the phytoplankton of marine and fresh water
ecosystems. They are single-celled organisms that have a silica (siliceous) skeleton consisting of
two overlapping halves (not unlike the two parts of a Petri dish).
o Observe prepared diatom slides and note the diverse morphology
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
Brown algae = a very large, multicellular, mostly marine group that prefer cool or cold water
temperatures in the intertidal zones and deep near shore waters. The dominant photosynthetic is
fucoxanthin. Some of these may grow to incredible size (e.g. Macrocystis spp, the giant kelp).
o Observe fresh and herbarium sheets of pressed examples of brown algae
 Find holdfast, stipe and blade (functions for each)
 Tidepools: giant kelp, sea potato, feather boa, rockweed, sargassum, sea palm
Alveolates = a large and diverse (from the perspective of a biology student). There are three phyla within
this taxon: dinoflagellates (Dinoflagellata), apicomplexans (Apicomplexa) and ciliates (Ciliophora).
 Dinoflagellates = are single-celled protists found in marine and fresh water ecosystems; they
comprise an important part of the phytoplankton.
o Ceratium (example dinoflagellate in our lab slides)  look for the flagellar groove and
flagella
 Some dinoflagellate species can cause red tides along coastal waters
 Ciliates = are freshwater species that use cilia to move and feed.
o Observe live and prepared specimens of Paramecium, Blepharisma and Stentor
 Find and know the functions: cilia, macronucleus, micronuclei, food vacuoles, oral
groove (Paramecium)
Rhizarians
 Forams = pore bearing amoeboid protist with multi-chambered test commonly comprised of
calcium carbonate.
o Examine prepared slides of foraminifera’s. Look closely at the tests. From what material
are the tests constructed? Can you see the foraminifera?
 Radiolarians = amoeboid protist with siliceous test that comprise marine zooplankton.
o Examine prepared slides of radiolarians. Draw at least two shapes of tests.
Supergroup Archaeplastida
 Red algae (Rhodophyta) = red color derives from a pigment called phycoerythrin. The plastids
containing this pigment are believed to have originated as cyanobacteria incorporated into the
red algae by primary endosymbiosis. Red algae prefer warmer coastal waters and some coralline
spp contributes to coral reefs.
o Examine the live and herbarium presses specimens.
o Tidepool: coralline algae
 Green algae (Chlorophyta) = possess chloroplasts and are probably closely related to the true
plants. It is the cells of chlorophytes that live symbiotically with fungi to create the “organisms”
we call lichens.
o Observe live and prepared slide of Volvox, a colonial chlorophyte
 Find the daughter colonies (how are they produced?)
 Tidepools= sea lettuce, dead man’s finger
Supergroup Unikonta
Amoebozoans
 Amoeba = observe live and prepared slides
o Find the nucleus, contractile vacuole, pseudopodia, food vacuole, plasmalemma
o Observe cytoplasmic streaming in the live specimen. Do not mix the container, amoebas
will be found living on the bottom of the container.
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Parabasalids
Euglenozoan
s
Excavata
Diplomonads
Stramenopiles
Diatoms
Golden algae
Brown algae
Alveolates
Apicomplexans
Ciliate
s
Forams
“SAR” clade
Dinoflagellates
Rhizarians
Cercozoan
s
Radiolarians
Green
algae
Chlorophytes
Charophytes
Land plants
Archaeplastida
Red algae
Amoebozoans
Slime molds
Tubulinids
Entamoebas
Opisthokonts
Fungi
Unikonta
Nucleariids
Choanoflagellates
Animals
Figure One. Proposed phylogeny of the Eukaryotes
As you examine the diverse samples notice how this taxon ranges from single-celled to multicellular, from
heterotroph to autotroph, and from structurally simple (single celled) to complex. Look for characteristics that are
shared with animals, plants and fungi; most evolutionary biologists believe the remaining multicellular kingdoms
arose from protist ancestors.
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Classification Scheme for the Eukarya (based on Reece et al., 2014)
Domain Eukarya
Super Kingdom Excavata
Kingdom Parabasala (trichomonads)
Lacking mitochondria
Trichomonas vaginalis, vaginal and urethral parasite
Kingdom Diplomonadida (diplomonads)
Two separate nuclei, no plastids, no mitochondria, multiple flagella
Giardia lamblia, human intestinal parasite
Kingdom Euglenozoa (euglenoids and kinetoplastids)
Flagellated, may be autotrophic, mixotrophic or heterotrophic
Phylum Euglenophyta
Euglena, organism seen in live in this lab
Phylum Kinetoplastida
Trypanosoma, causes African sleeping sickness, Chaga’s disease
Super Kingdom “SAR” Clade (Stramenopila, Alveolata, Rhizaria)
Kingdom Stramenopila
Phylum Bacillariophyta (diatoms)
 most diverse algal phylum over 10,000 marine and fresh water species, secrete
silica tests (shells)
Phylum Chrysophyta (golden algae)
 combination of yellow and brown pigments, unicellular species of ponds and
lakes
Phylum Phaeophyta (brown algae)
 multicellular marine algae usually known as sea weeds
Phylum Oomycota1 (water molds)
Phytophthora infestans (potato blight)
Phytophthora ramorum (sudden oak death)
Kingdom Alveolata (Membrane bound alveoli under cell surface)
Phylum Dinoflagellata (dinoflagellates)
 Microscopic algae that form the basis of most marine food chains
Phylum Apicomplexa (Parasites of animals)
Plasmodium, causes malaria in humans
Phylum Ciliophora (ciliates)
 Move by undulating cilia, feed by ingesting bacteria or other protists, marine or
freshwater
Paramecium, Stentor, Blepharisma
Kingdom Rhizaria
Phylum Radiolaria (radiolarians and heliozoans)
Phylum Foraminifera (foraminiferans)
Phylum Cercozoa
Super Kingdom Archaeplastida
Kingdom Rhodophyta (red algae)
 Mostly marine algae, mostly multicellular, possess unique red phytopigments
Kingdom Chlorophyta (green algae)
 unicellular and filamentous algae, fresh water and marine
Kingdom Charophyta (Charophyceans)
Kingdom Plantae
Phylum Hepatophya (liverworts)
Phylum Anthocerophyta (hornworts)
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Phylum Lycophta (lycophytes: Lycopodium)
Phylum Pterophyta (whish ferns, horsetails and true ferns)
Phylum Ginkophtyta
Phylum Cycadophtyta
Phylum Gnetophyta (Mormon tea, Welwitschia)
Phylum Coniferophyta (conifers)
Phylum Anthophyta (flowering plants)
Super Kingdom Unikonta
Kingdom Amoebozoa
1
Reece, et. Al. 2014 does not acknowledge the Phylum Oomycota;
however, we need a place holder for this important
group.
Phylum Myxogastrida (plasmodial slime molds)
Phylum Dictyostelida (cellular slime molds)
Phylum Gynamoeba
Phylum Entamoeba
Kingdom Nuclearida
Kingdom Fungi
Phylum Chytridiomycota
Phylum Zygomycota
Phylum Glomeromycota
Phylum Ascomycota
Phylum Basidiomycota
Kingdom Choanoflagellata
Kingdom Animalia
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