Predict how phospholipids would arrange themselves if they were placed into a nonpolar solution
A. The phospholipid heads would orient
toward the solution.
B. The phospholipid tails would orient toward
the solution.
C. The phospholipids would form a bilayer.
D. The phospholipid would form a liposome.
Answer Key: B
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Researchers studying the rigidity and flexibility of the cell envelope used chemotaxis to measure the ability of microbes to squeeze through tight spaces. E. coli, a gram-negative bacterium, was able to traverse narrower channels than B. subtilis, a gram-positive microbe, even though both cells are the same size when grown without restriction. E. coli has the more flexible cell envelope because
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What is meant by adaptation from standing genetic variation in natural populations?
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