Answer
The cell membrane is made up of a variety of lipids, most of them being phospholipids, that arrange themselves in what is known as the "phospholipid bilayer." This bilayer consists of phospholipids with hydrophilic, or water loving, heads in contact with the fluids outside of the cell, and hydrophobic, or water hating, tails facing inwards. This specific amphiphilic structure is what allows for the fluidity of the cell.
Work Step by Step
The cell member is perhaps one of the most important parts of the cell, being responsible for many of the functions vital to our survival. 75% of the lipids in the cell membrane are phospholipids. These molecules, with a hydrophilic, phosphate-containing head, and a hydrophobic tail, allow for the fluidity and free movement of the cell, which is what enables small proteins to enter the cell. The other part of the cell membrane is made up of cholesterol, a molecule that helps keep the phospholipids in place, thus creating a more firm, selective, membrane. Together these two molecules, among with others, maintain the overall structure of the plasma membrane, and gives the cell the ability to carry out important functions.
