Answer: Directional selection occurs when individuals with traits on one side of the mean in their population survive better or reproduce more than those on the other. ... Directional selection does the “heavy lifting” of evolution by tending to move the trait mean toward the optimum for the environment.
A liquid can not be a crystalline
The phospholipids form a bilayer in water because of hydrophobic and hydrophilic interactions. The hydrophobic tails do not interact with water
