Gen Bio II- Prokaryotes Notes

Archaea prokaryotes v eukaryotes external structures

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Unformatted text preview: ree types •  TransformaDon •  TransducDon •  Bacterial conjugaDon Horizontal Gene Transfer Among Prokaryotes •  TransformaDon –  Uptake of free DNA –  Process was instrumental in determining that DNA is geneDc material –  Cells that take up DNA are competent •  Results from alteraDons in cell wall and cytoplasmic membrane that allow DNA to enter cell Figure 14.26 14 1/29/14 GeneDc RecombinaDon and Transfer •  Horizontal Gene Transfer Among Prokaryotes –  TransducDon •  Direct transfer of DNA into a bacteria via viral vector Bacterial ConjugaDon Cell to cell contact through the use of a pilus required Figure 7.34 Bacteria v. Archaea •  •  •  •  •  •  Cell Size & Shape Bacteria Cell Structure Genome Growth GeneDc Transfer Bacteria v. Archaea Cell Stricture –  External Structures –  Cell Envelope –  Cytoplasm •  Prokaryotes v. Eukaryotes 15 1/29/14 External Structures of Archaea •  Glycocalyces –  FuncDon in the formaDon of biofilms –  Adhere cells to one another and inanimate objects •  Flagella –  Consist of basal body, hook, and filament –  Numerous differences with bacterial flagella •  Fimbriae and Hami –  Many archaea have fimbriae –  Some make fimbriae- like structures called hami •  FuncDon to a_ach archaea to surfaces Archaeal Cell Envolope •  Most archaea have cell walls –  Do not have pepDdoglycan –  Contain variety of specialized polysaccharides and proteins –  Ferroplasma & Thermoplasma have no cell wall •  All archaea have cytoplasmic membranes –  Maintain electrical and chemical gradients –  Control import and export of substances from the cell Cytoplasm of Archaea •  Archaeal cytoplasm similar to bacterial cytoplasm –  Have 70S ribosomes –  Fibrous cytoskeleton –  Circular DNA •  Archaeal cytoplasm also differs from bacterial cytoplasm –  Different ribosomal proteins –  Different metabolic enzymes to make RNA –  GeneDc code more similar to eukaryotes 16 1/29/14 Archaea •  Much more known about bacteria •  Extremophiles •  Two Phyla with undetermined higher taxa •  Crenarchaeota –  No medically relevant archaea –  Organisms that thrive in severe physically or chemical environments –  A reflecDon of how li_le is known –  Many require temperatures of 80˚C or higher (176˚F) –  OpDmum pH range is 1 or 2 •  Euryarchaetoa –  Extreme halophiles (love salt) •  Photosynt...
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This document was uploaded on 03/18/2014 for the course BIO 1312 at Dallas.

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