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Chapter 11 (11A- The protozoan (Classification of protozoan (phylum…

- - - - enclosed in flexible membrane
        
        When moving or feeding, they will form numerous extensions called pseudopodia that function as “false feet.”
        
        When dormant, they may be nearly spherical.
      - live in a variety of habitats, including fresh water, the sea floor, and the human mouth and intestines.
      - Type of Sarcodina
        
        Amoeba
        
        Types of cytoplasm- the endoplasm and the exoplasm
        
        Contractile vacuoles collect and eliminate water, regulating homeostasis between the amoeba and its environment.
        
        amoeboid movement- creates bulges to move its body forward
        
        taxes- response to stimuli
        
        When an amoeba reaches maximum size, it undergoes binary fission,
        
        Entamoeba histolytica can cause a severe intestinal infection called amoebic dysentery.
    - - The characteristic that distinguishes this group is the possession of multiple hairlike projections called cilia.
      - Types and examples
        
        genus Paramecium
        
        pellicle, a firm yet flexible protein-rich covering that is outside the cell membrane.
        
        macronucleus- copies of genes probably aid the high metabolism typical of most ciliates and are important in asexual reproduction.
        
        gullet- food vacuole
        
        copies of genes probably aid the high metabolism typical of most ciliates and are important in asexual reproduction.
        
        Reproduce asexually by Binary fission and sexually by conjugation
    - - as adults, they do not have pseudopodia, cilia, flagella, or any other special structures for locomotion.
      - nucleus divides and cytoplasm covers around it, the organism breaks apart and each nuclei becomes a spore
      - Types and examples
        
        Plasmodium, the genus that causes malaria,-- spread by masquitos
        
        parasite enters red blood cell and reproduce, once blood cell pop-- disease spread
    - - flagella
      - unicellular and live in ponds and lakes,
      - live off of decaying organisms or small organisms
      - reproduce asexually by binary fission
      - example and types
        
        African sleeping sickness, or trypanosomiasis
        
        African sleeping sickness, or trypanosomiasis
- - - - spindle-shaped organisms has two anterior flagella for locomotion—
      - survives primarily on the products of photosynthesis.
      - euglena
        
        saprophytic, absorbing dissolved food from the surrounding environment
        
        euglenoid movement, euglenas can propel themselves with a wormlike motion.
    - - Large starch granules can often be found around a protein-containing organelle, the pyrenoid
      - contain chlorophylls a and b and carotenoids
    - - contain large amounts of carotenoids that give them their golden color, as well as chlorophylls a and b.
      - Members of the genus Dinobryon exist as single flagellated cells, but they can also join to form a colony.
      - Vaucheria is a common genus characterized by long filaments.
      - the filaments lack interior divisions into separate cells. As a result, they are multinucleate.
    - - important in the food chain and are responsible for more oxygen-supplying photosynthesis than any other group of organisms.
      - store their food as oil that often appears as large drops in the cell.
      - Diatomaceous earth, a crumbly substance made of diatom shells, is found in many parts of the world.
      - Some diatoms reproduce sexually follow- ing several asexual cell divisions
    - - grow attached to rocks or to the ocean floor.
      - contain chlorophylls a and c and a large amount of the pigment fucoxanthin
      - Algin, a gelatinous coating found on many brown algae, serves as a thickener in commercially produced ice cream and other foods.
      - Brown algae produce sperm and ova in multicellular antheridia and oogonia.
    - - grow in shallow, warmer waters, but sometimes they are found at a depth of over 150 m
      - absorbs calcium carbonate which is important in building some reefs and islands.
      - carrageenan-are used in foods, cosmetics, and the gelatin shells of drug capsules.
      - agar, a gelatinous substance used in growing bacteria.
    - - possess two flagella of un- equal length. One flagellum is normally kept in a groove around the algal cell; the other is used for movement.
      - Yellowish brown pigments color these algae.
      - bioluminescent- when the water is disturbed, can emit enough light to cause the sea to glow.
      - Most dinoflagellates are marine, but some species live in fresh water.
- - - - two-phased life cycle.
        
        1) the feeding phase, the cells look like amoebas, moving about using pseudopodia and eating bacteria and organic matter. appear as slimy masses that can be white, yellow, or red..
        
        2)primarily a reproductive phase in which funguslike structures called fruiting bodies are formed. These fruiting bodies produce spores.
      - cellular slime molds-- If food becomes scarce, they gather together into a single colony called a pseudoplasmodium that looks like a slimy slug.
      - Acellular or plasmodial slime molds-- start their life as amoeba-looking cells. During the feeding phase, members of this phylum form an amorphous structure called a plasmodium
        
        A plasmodium is multinucleate—all the cell walls have dissolved and the thousands of nuclei are floating around in a mass of cytoplasm.
    - - sexual reproduction, the water mold has cells that develop sperm and ova. Fertilization tubes grow between these cells, allowing the haploid gametes to form diploid zygotes. The zygotes develop into new organisms.
      - asexual reproduction, special cells called sporangia produce flagellated zoospores that swim away in search of food. Once food is located, the zoospores develop into new organisms.
      - cause of many kinds of blight, a disease of plants that causes rapid destruction of the leaves and stems, resulting in the death of the plant.