I.  Background
     A)  World Health Organization - top 5 parasitic diseases are among the top 20 microbial causes of death  in the world.
     B)  There are > 5 million cases of malaria, schistosomiasis, amoebiases, hookworm  and African trypanosomiasis
        reported each year in developing countries.
     C)  Emerging eukaryotic pathogens
          1. Pneumocystis carinii (fungus) - pneumonia; leading cause of death in AIDS patients
          2.  Cryptoporidium parvum (protozoan) - diarrhea
          3.  Cyclospora (protozoan) - diarrhea
          4.  Dog hookworm found to infect humans
          5.  A new tapeworm

II.  Fungi - structure and life cycle
     A.  Fungal colonies - called vegetative structures; cells concerned with growth and metabolism
     B.  Body of fungus - thallus (thalli); consists of long filaments of cells joined together called hyphae;
        filamentous mass also called a mycelium.   Figure 12. 1.
          1. can grow to immense proportions - hyphae of a single fungus in Michigan was found to extend across 40 acres.
          2.  Septate hyphae - cross-walls between cells
          3.  Coenocytic hyphae - no cross-walls, continuous cytoplasm.
    C.  Fungi grow by elongation at tips of hyphae.
    D.  Reproduce by forming spores
    E.  Yeasts
        1.  nonfilamentous, unicellular fungi; spherical or ovoid in shape.
        2.  Reproduce by fission or budding
        3.  Some are Dimorphic - can switch between filamentous growth or yeast growth
    F. Importance of fungi
        1.  Incidence of fungal infections is on the rise, especially in immune-compromised people.
        2.  Also, many fungi are plant pathogens.
        3.  Fungi are also beneficial as decomposers, symbionts, in industry.
    G.  There are >100,000 species of fungi, <100 are pathogenic.
    H.  Nutritional Adaptations of fungi
        1.  Grow in environments hostile to bacteria
        2.  Absorb nutrients (rather than ingest)
        3. Prefer pH 5 for growth
        4.  Molds are aerobic; most yeast are facultative anaerobes.
        5. Can grow in high sugar and salt
        6.  Can grow in drier environments than bacteria
        7.  Require less nitrogen than bacteria
        8.  Can metabolize complex carbohydrates, such as wood (lignin).
    I. Life cycle of filamentous fungi
        1. Asexual and sexual reproduction
        2.  Four Divisions of fungi
            a.  Ascomycota - characterstics; life cycle Figure 12. 7
            b.  Basidiomycota - characteristics; life cycle Figure 12.8
            c.  Zygomycota - characteristics
            d.  Deuteromycota - characteristics

III.  Algae - structure and life cycle
    A.  Some unicellular, some filamentous, others are plant-like
    B.  Mostly aquatic - in cool temperate waters; ocean
    C. Photosynthetic
    D.  Groups of algae
        1.  Brown Algae - kelp; macroscopic; coastal waters
            a.  Algin
        2.  Red Algae - delicately branched; deeper in ocean; red color absorbs blue light for photosynthesis
            a.  Agar and carrageenan
        3. Green algae - cellulose cell wall; store starch and have similar chlorophyll as plants; plant progenitors
               a.  Life cycle of the unicellular green alga, Chlamydomonas  Figure 12.11
        4.  Diatoms - unicellular or filamentous, pectin and silica cell wall.
        5.  Dinoflagellates - unicellular algae called plankton; cellulose in plasma membrane; produce neurotoxins - red tide.
        6.  Euglenoids - protein pellicle; unicellular, flagellated, eye spot.

IV.  Other Eukaryotic Microorganisms
    A.  Read about Lichens and Slime Molds (will be on test).
    B.  Protozoa - unicellular, not photosynthetic, live in water or soil.
        1.  Vegetative stage - trophozoite, feeds on bacteria and small particulate nutrients.
        2.  >20,000 species only a few are known pathogens.
        3.  Asexual reproduction by fission, budding or schizogony (multiple fission)
        4.  Sexual reproduction - conjugation and trading haploid nuclei.
        5.  Some form a cyst for survival in adverse conditions.
        6.  Most are aerobes; some are anaerobes; transport food across membrane or actively engulf.
        7.  Examples
            a.  Amoeba
            b.  Flagellates
            c.  Ciliates
            d.  Apicomplexans - obligate intracellular parasites; complex life cycle
                   i.  Life cycle of Plasmodium (Malaria) Figure 12. 21.