Question

They are more gelated and highly ordered than the surrounding more fluid and disordered regions in artificial membranes that consist primarily of phosphoglycerides. They contain higher concentrations of sphingolipids and cholesterol and certain proteins become concentrated within them. What are they?

a) lipid islands
b) collections
c) lipid rafts
d) lipid domains
e) dense bilayers

Answer 1

Lipid rafts are ordered regions in artificial membranes enriched with sphingolipids, cholesterol, and certain proteins, and they play a role in cell signaling and protein trafficking. Therefore, the correct option is C.

Step-by-step explanation:

The regions in artificial membranes that are more ordered and contain higher concentrations of sphingolipids, cholesterol, and certain proteins compared to the surrounding more fluid and disordered regions are known as lipid rafts. These structures are functional aspects of cell membranes, helping to organize cell signaling and protein trafficking. Lipid rafts serve as platforms for a variety of cellular processes and are distinguished from the more disordered phospholipid areas of the bilayer due to their unique lipid composition and higher degree of saturation.