Unit 2:  Kingdom Protista
1.  State the estimated number of named species and briefly describe their distribution.
2.  Summarize the classification scheme of the Kingdom Protista.
3.  Identify the key characteristics used to separate protozoan animals into their individual phylum and class.
4.  Describe the symbiotic relationships that the protozoans commonly employ for survival.
5.  Describe the primary means with which the protozoans acquire food.
6.  Discuss both the economic benefits and harm of the animals in this kingdom.
7.  Describe and discuss amoeboid movement with pseudopodia as well as locomotion employing cilia and flagella.
8.  State the two prevailing hypotheses of how cilia work.
9.  Define the term acellular, and tell why it may be more suitable than the term one-celled in describing protozoa.
10.  Describe the action and function of contractile vacuoles.
11.  Define organelle.  Describe the form and function of organelles observed in the laboratory specimens.
12.  Describe the coordinated mechamisms and taxis (taxic responses) of these genera:  Amoeba, Paramecium, Euglena and Plasmodium.
13.  Outline the life cycle of Entamoeba histolytica , state the importance of amoebiasis, and describe control measures.
14.  Describe cyst formation in protozoa and its effect on life cycles and distribution.  Utilize the flagellate of the genus Giardia as an example.
15.  State the significance of the foraminifera and radiolaria in the formation of layers in the earth's crust.
16.  Use the diversity among different species of flagellated protozoa to justify the idea that flagellates may represent the primitive group from which other protozoa, the sponges and plants may have evolved.
17.  Describe the variation in asexual and sexual reproduction in different groups within the kingdom.
18.  Outline the life cycle of Trypanosoma gambiense, state the importance of African sleeping sickness, and describe control measures.
19.  Outline the life cycle of Plasmodium vivax, state the importance of malaria, and sexcribe control measures.
20.  Differentiate between the classes Phytomastigophorea and Zoomastigophorea.
21.  Explain how gas exchange and excretion occur in protozoa, and why special structures for these functions are not necessary.
22.  Describe the importance of protozoa in aquatic food chains.
23.   List the possible habitats of members of the different classes of protozoa.

Resources:  Text:  Animal Diversity, Chapter 5
Protozoan Internet Sites:
http://gemini.tntech.edu/~elmorgan/111/protista1.html

http://www-biol.paisley.ac.uk/courses/tatner/biomedia/units/prot1.htm
http://taxa.soken.ac.jp/WWW/PDB/LINK/oversea.html
http://www.mhhe.com/hickmanad4e

 Protozoans-  Kingdom Protista

    -microscopic
    -live individually (Euglena) or in simple colonies (Volvox)
    -unicellular but not "simple"
    -no tissues or organs; organelles, division of labor
    -protoplasmic level of organization

Why not Kingdom Animalia?
    -no cell wall
    -at least one motile stage of life cycle
    -injest food

Estimates reach 70,000 as to # of species described, wide distribution; wet, moist habitats
    -fresh, marine and brackish waters
    -sewage
    -moist soil
    -parasitic

**Classified according to Kinds of structures used for movement and food gathering

Groups we will concentrate on (pg 101-102, note differences in names for Sarcomastigophora)

Phylum Sarcomastigophora "whip bearing"
    Sub Phylum Mastigophora- flagellates  ( Euglena, Volvox, Trypanosoma)

    Sub Phylum Sarcodina- Pseudopodia (false foot)  (Amoeba)

Phylum Ciliophora- Ciliates  (Paramecium )

Phylum Apicomplexa- spore forming
        Class Sporozoa- parasitic  (Plasmodium )

Ecology
Symbiotic relationships
    1.  Commensals- live on or in other organisms without causing harm.  Host unaware of
        their presence.
    2.  Mutuals- ciliates in gut of animals  (ex. those in gut of termites)

    3.  Parasites- amoebic dysentary, malaria, African sleeping sickness, Giardia,  Desert
        Storm
        *usually why you are encouraged not to drink the water!!

    4.  Solitary- dinoflagellates ---> Red tide pg 99, soil protists

Nutrition
    Holophytic- autotrophic, produce own food, photosynthesis w/ chlorophyll and
        chloroplasts (Euglena)

    Saprozoic- absorb preformed organic nutrients from environment, sewage treatment

    Holozoic- injestion of solid or liquid food through "mouth"
        cystopharynx (cell mouth), Phagocytosis (Amoeba) browsers, hunters, trappers
        digestion in food vacuoles; lysosomes carry digestive enzymes

Economic Considerations
    1. water purification systems (both to protect you and for them to clean water system)
    2. Health
    3. food sources (red tide)

GENERAL PROTISTA CHARACTERISTICS (Summaries Pgs 87)
    A. Locomotion
        1. Amoeboid movement w/ pseudopodia (false foot)  Pg 88

            inner endoplasm
            outer ectoplasm  :difference between them is their state of solidity

                Endo- plasma sol, fluid state
                Ecto- plasma gel, semi-solid state

                -direction of movement determined by movement of pseudopodia.

                -actin & myosin- changes in these proteins determine differentiation between
                    sol/gel

    PSEUDOPODIA  pg 88
 
 
 
 
 
 
 

      -----> Direction of movement; cytoplasmic streaming

                -tube formation
                -opposite takes place at "tail end"

    2.  Flagella/cilia  pg.86-87
        -not limited to locomotion; also responsible for movement of material into
            organism (feeding) or respiration.  (sperm, cells of upper respiratory tract)

        -cilia much shorter than flagella
        -ciliary motion  1-->5 effective stroke;  6-->8 recovery stroke  Coordinated
            beating

           How cilia work- two hypotheses
                1.  contraction/relaxation of microtubules
             **2.  sliding microtubules
                    -powered by energy release by splitting ATP
                    -microtubules slide relative to each other
 

REPRODUCTION pg 91-92
    Asexual- produces clones, two daughter cells that are genetically identical only
        chance of variation would be chance mutation

    Binary fission- nuclear fission is mitotic  Paramecium- transverse (text)

    Budding- similar to fission but not equal cytokinesis

    Multiple fission (schizogony)- nucleus divides repeatedly then cytokinesis.  Creates as
        many cells as there are nuclei.  Sarcodina, Sporozoea

    Spore formation (sporogony)- Plasmodium
        -multiple division of nucleus and cytoplasm
        -spore extremely resistant
        -takes place after fertilization

    Colonial-  Volvox  (can also be sexual w/ gametes)

    Sexual- meiosis (gamete formation- haploid)
        Conjugation- Paramecium ciliates unique, no free swimming gametes, swap micronuclei

        Syngamy- individual gamete fertilizes another gamete to form gamete (not predominant

        Autogamy- gametes produced by meiosis fuse within organism that produced them

        Parthenogenesis- development from gamete w/o fertilization (haploid)

PHYLUM SARCOMASTIGOPHORA (fleshy whip bearer)  pg 92-94, 98-99
    Sub Phylum Mastigophora - "whip bearing"  flagellates- flagella primary mode of locomotion
        -marine and freshwater
        -most primitive protozoan
        -animal and plantlike forms

        Class Phytomastigophorea- plant (phyto) bearing whip  Euglena
            *producers, contain chlorophyll
            *autotrophs (primarily), some saprozoic or holozoic or combinations
                -Imperfect autotrophs- cannot make B12, obtains by pinocytosis
            *positively phototrophic (eyespot, stigma) although avoids intense light
            *CO2 source of carbon
            *flagella movement varies; spiral most prevalent, can push or pull
            *Volvox (colonial) non parasitic
            *Volvox- capable of sexual reproduction (response to depleated nitrogen)

        Class Zoomastigophorea- animal bearing whip
         Trypanosoma (sleeping sickness) blood parasite
                * "colorless", no chlorophyll
                *holozoic, saprozoic, or parasitic
                *one to many flagella w/ varied forms of beating
                *binary fission- longitudinal

    Sub Phylum Sarcodina  pg 99-- Amoebas, foraminiferans, radiolarians
        1. PSEUDOPODIA, amoeboid movement
       *2.  flagella in developmental stages
        3.  holozoic, saprozoic, few parasitic (Entamoeba)  -phagocytosis ---> vacuole/lysosomes
        4.  Asymmetrical
        5.  May posses shell (TEST) this can be symmetric and relatively large
        6.  diverse ecology, found everywhere

            Foraminiferans- shelled (test);  marine (both pelagic and benthic)
                -test formed by secreations of calcium carbonate (CaCO3)
                -thread like pseudopodia extend out holes in shell for prey capture and to
                    increase surface area for diffusion
                -multichambered shells

            Radiolarians- marine, planktonic
                -test/shell make of silica
                -among oldest known fossils

                ***Forams and Radiolarian deposits extensive Limestone and chalk deposits,
                    White Cliffs of Dover

PHYLUM APICOMPLEXA  pg 94-95- organelles in tip (apex) of organism
    -all parasitic, apical complex aids entry into host
    -flagella and cilia present in developmental stages, otherwise absent
        Class Sporozoea, spore producer
         Plasmodium (malaria) Sickle Cell Anemia, Toxoplasma (cats)
            Congenital toxoplasmosis Pg 95

PHYLUM CILIOPHORA  pg 95-98 - cilia bearing (cilium- eye lash)  Paramecium
    -posses cilia sometime during life
    -2 types of nuclei
        macronucleus- metabolism, synthetic, development
        micronucleus- reproduction

    -cytostome (cytopharynx)= mouth
    -reproduction --->   Asexual- binary fission
        Sexual- conjugation (unique to ciliates)
    -freshwater, marine
    -holozoic, few parasitic, ciliary feeders

    -cell membrane   pellicle- living structure, contains organelles, cilia extends through it
        trichocysts- used in defense and prey capture
    -vacuoles- found in all freshwater (hypotonic) and some marine
 
 

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