EVERYDAY SCIENCE

Detailed explanation-1: -1: A phospholipid consists of a head and a tail. The “head” of the molecule contains the phosphate group and is hydrophilic, meaning that it will dissolve in water.

Detailed explanation-2: -All of the lipid molecules in cell membranes are 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.

Detailed explanation-3: -The hydrophilic, or “water-loving, ” portion of a phospholipid is its head, which contains a negatively charged phosphate group as well as an additional small group (of varying identity, “R” in the diagram at left), which may also or be charged or polar.

Detailed explanation-4: -The phosphate group is the negatively-charged polar head, which is hydrophilic. The fatty acid chains are the uncharged, nonpolar tails, which are hydrophobic.

Detailed explanation-5: -A phospholipid consists of a hydrophilic (water-loving) head and hydrophobic (water-fearing) tail.