How to prepare for your annual encounter with confusion. Daylight Saving Time ends Sunday at 2 a.m., which means that weâre all going to spend a few minutes scratching our heads trying to figure out whether weâre gaining or losing an hour of sleep. Save yourself the trouble and let TIME break it down for you.
For example, plasma membrane proteins carry out functions as diverse as ferrying nutrients across the plasma membrane, receiving chemical signals from outside the cell, translating chemical signals into intracellular action, and sometimes anchoring the cell in a particular location (Figure 4).
Membrane proteins are important for transporting substances across the cell membrane. They can also function as enzymes or receptors. On the extracellular fluid side of a cell membrane, you find carbohydrates. They help a cell to be recognized as a certain type of cell and are important for holding cells together.