All of the liquid molecules in cell membranes amphipathic (or amphiphilic) -that is, they have a hydrophilic ("water loving") or polar end and a hydrophobic ("water fearing") or nonpolar end. The most abundant membrane lipids are the phospholipids. These have a polar head group and two hydrophobic hydrocarbon tails.
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Answer:
Mutations are important to the evolution of a species because is creates new DNA for a certain gene, creating a new allele.
(Answer taken from https://www.apsnet.org/edcenter/disimpactmngmnt/topc/PopGenetics/Pages/Mutation.aspx#targetText=Mutation%20plays%20an%20important%20role,gene%2C%20creating%20a%20new%20allele.)
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