9.1: Introduction
- Page ID
- 138430
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The plasma membrane, also called the cell membrane, has many functions, but the most basic one is to define the borders of the cell and keep the cell functional. The plasma membrane is selectively permeable. This means that the membrane allows some materials to freely enter or leave the cell, while other materials cannot move freely, but require the use of a specialized structure, and occasionally, even energy investment for crossing.
Understanding the chemistry of the plasma membrane's makeup is vital to understanding how it works as a selective barrier and to how it interacts with other molecules around it, such as proteins and carbohydrates. Remember from our earlier discussions, that the plasma membrane is made primarily of phospholipids. Complete the activity below to review content related to the chemistry of phospholipds.