TABLE OF CONTENTS Life as we know it requires matter to enter and leave cells. This transport is accomplished in a number of ways, and central to this is the flexibility of cell membranes. This flexibility arises because, structurally, cell membranes are liquid crystalline phases. This chapter explores why living organisms use liquid crystalline phases as the structure of choice to achieve some of their necessary functions and how serious diseases may result when these liquid crystalline phases or their chemical components are modified. It will introduce the relationship between lyotropic liquid crystals and life. The following questions will be addressed:
Why should liquid crystalline phases be necessary for life?
Where do liquid crystalline phases exist in cells?
How are some diseases related to Liquid crystalline phases and phase transitions?
Life, by its very nature, puts constraints on the structures that will allow it to exist. For example, our bodies are largely composed of water; yet our overall shape and size changes slowly except under catastrophic conditions. Our skin is elastic but doesn t stretch too much, and our bones are strong and rigid. Moreover, even in specialized cells such as red blood cells, which are in an essentially aqueous environment, there is still separation between the inside contents of the cell and the surrounding, outer fluid. Detailed studies of cells and the components of cells reveal ordered regions in these objects. What structures are simultaneously rigid and flexible, able to provide an orienting substrate, and act as membranes that...
