Mastering Microbiology: Microbiology Now Chapter 5 Google Chrome https:// sessio
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Question
Mastering Microbiology: Microbiology Now Chapter 5 Google Chrome https:// session.masteringmicrobiology.com 6762404 BIOS 350 SP15 12 PM robiology Now Chapter 5 Question Part C Cell membranes and temperature Hyperthermophiles are organisms that thrive at extremely high temperatures. What sorts of specializations might they have to survive in such high temperatures? Choose all of the correct answers. increased use of isoprene units instea of fatty acids cell membranes with more cholesterol cell membranes with a higher degree of unsaturation monolayer membranes that link one side to the other for stability extremely heat stable proteins that function best at high temperatures cell membranes with long chain fatty acids Submit Hint My Ans Up Revi In the original article (E 2013) referenced in the introductory passage, the authors state that the peptidoglycan cell wall was probably present in the last common ancestor of modern bacteria, one existed. However, in order to build rrington, the cell wall, its components must cross the cell membrane Part D Cell wall synthesis and crossing the plasma membrane L-form bacteria rely on their cell membrane as their protection from the external environment, determining what can move in and out of the cell. Bacteria with cell walls have additional protection, but need to synthesize the peptidoglycan precursors within the cell and then transport them across the membrane to maintain or expand the cell wall. The peptidoglycan precursors require assistance in moving across the membrane, which is accomplished by a hydrophobic molecule called bactoprenol. Why is mportant for peptidoglycan precursors to be sufficiently hydrophobic in order to cross the cell membrane? Choose the best answer. Hydrophobic molecules are able to form channels that allow large materials, like peptidoglycan precursors, to pass through the membrane The phosphate groups in the phospholipid membrane are hydrophobic, so itis easier for hydrophobic materials to pass through the membrane No materials can cross the membrane without assistance from helper molecules, Which are often hydrophobic The hydrocarbon tails in the phospholipid membrane are hydrophobic, so it is easier for hydrophobic materials to pass through the membrane Submit Hint My Ans Up Revi Many properties of these bacteria result from basic membrane properties, rather than additional specialized structures. Without a cell wall, the effects of the surrounding environment on the membrane become extremely importantand osmotic conditions heavily influence the microbes. 5:05 PM EN 2/15/2015Explanation / Answer
Part C)
To survive in higher temperatures hyperthermophiles posess increased use of isoprenoids instead of fatty acids, Cell meebranes with high levels of cholesterol and higher degree of unsaturation and also contain extremely heat stable proteins to function in higher temperatures.
part D)
The peptidoglycan precursors cannot move out of cell membrane without assistance of bactoprenol, a hydrophobic molecule. The mechanism is unknown but still it is thought that the hydrophobic molecules form channels that allow the passage of large molecules like peptidoglycan presursors.