Importance of cholesteral to plasma membranes?

Answer 1

Cholesterol is vitally important to cellular membranes because it helps to keep the membrane fluid at lower temperatures. The membrane is made up of a phospholipid bilayer which are straight chain fats, and these fats become solid at low temperatures. Cholesterol is a bent chain steroid fat that becomes solid at a lower temperature than the straight chain fats do. So when the cellular membrane is subjected to lower temperatures, the cholesterol is able to keep the membrane fluid so that molecules can still pass through it during transport. Cholesterol is also used in many different cell-signaling activities.