Question:
I. Cite at least 4 examples of structural & functional diversity among protists
Answer:
a) Protists are more diverse than all other eukaryotes and are no longer classified in a single Kingdom. Most protists are unicellular, some are colonial or multicellular. Protists include photoautotrophs, heterotrophs, & mixotrophs. Most species are aquatic, but others are found in moist terrestrial habitats. Some species are exclusively asexual; others reproduce asexually.
Question:
II. Immediately after a eukaryotic cell ingests a gramnegative cyanobacterum dirung primary endosymboisis, how many membranes separate the cytoplasm of the bacterium from the fluid outside the eukaryotic cell? Identify each membrane.
Answer:
a) Some biologists hypothesize that mitochondria and plastids are descendans of alpha proteobacteria and cyanobacteria, respectively, that were engulfed bt itger cekks abd became endosymbionts. The plastid-bearing lineage enventually evolved into red algae and green algae. Other protist groups evolved form secondary endosymbiotic events in which red algae or green algae were themselves engulfed.
Thursday, November 29, 2007
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