Summary Cell Biology; Cell membrane Review

Explain how the structure and properties of phospholipids help to maintain the structure of cell
membranes:


The cell membrane is the biological structure, which separates the inner and outer cellular

fluids in the cell, thus making sure only particles that the cell needs are permitted to enter in the

cell. The building blocks of cell membranes are types of complex lipids called phospholipids,

which are composed of two fatty acids attached to a glycerol head. This glycerol molecule is

attached to a phosphate group and forms the hydrophilic end of the membrane. The arrangement

of the phospholipids is essential for the functions that they serve for the membrane. The

hydrophobic and hydrophilic ends of the molecule regulate what passes through the membrane,

making it selectively permeable. Hydrophobic and hydrophilic ends of the phospholipid are the

reason membranes are composed of a bilayer, which provides extra protection. The ability of the

phospholipids to change their position either through lateral diffusion or flip flop makes the

membrane flexible, which makes it possible for certain cell, red blood cells, for example, to pass

through narrow spaces.