Monday, February 21, 2011


Yunsu Y.

↑Parmecium ↑

  • Most protists are single celled, but there are still some that are multicellular.

  • They are eukaryotes and more complex than prokaryotes.

  • 2 Theories of how eukaryotic cells evolved :

  1. All organelles evolved from inward folds of the plasma membrane or endocytosis. ----except mitochondria and chloroplast, because they have their own DNA.

  2. Endosymbiosis

  • developed by Lynn Margulis

  • chloroplast and mitochondria evolved from small prokaryotes that established residenc within other, larger host prokaryotes.----the host cell may have injested theses for food and if remained alive, continued to perform respiration within cell.

  • Like before, most are unicellular, but some are colonial or mulitcellular. (those two are different.)

  1. 4 categories of protists:

  • protozoans

  • slime molds

  • unicellular algae

  • seaweeds

  1. Protozoans

  • Ingest food and have to live in the water, wet soil or watery enviornment inside animals.

  • They have flagellates: one or more to move. Free living but some are parasitic

  • Amoeboas: move by pseudopodia-extensions of cytoplasm.

  • Forams: move with pseudopodia and components of limestone.

  • Apicomlexans: all parasitic and named for an apparatus at their apex.

  • Ciliates: use cilia to move and feed.

2. Slime molds:

  • may look like fungi but not closely related.

  • decomposers

3. Unicellular Algae:

  • have chloroplast

  • components of plankton-communities of organism, microscopic and drift or swim near surface of ponds and oceans.

  • planktonic algae=phytoplankton

  • 3 groups:
-Dinoflagellates: 2 flagella, blooms cause red tide.

-Diatoms: glassy cells walls with silica-used to make glass.

-Green algae: mostly in freshwater lakes and ponds. Most closely related to true plants but still towards the protists. Volvox is a colony of flagellated cells.

4. Seaweeds

  • multicellular marine algae

  • slimy rubbery substances that cushion bodies against waves

  • Different colors like: green, red, brown

  • Used fro food: found commonly in Asian food, soups, wraps, sushi.
-some have polysaccharides, humans cannot digest.

  • Also used for thickeners: pudding, ice cream, salad dressing, and Gel agar in petri dishes.

After notes we worked on U.P pg 27-31, whatever that was not finished was homework.

HW: pre-lab U.P pg 39-43, be prepared on Monday, know what we are doing. Nature Due 3/4

Next Scribe: Davin L.

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