Answer:
Cholesterol
Step-by-step explanation:
Cholesterol is a lipid molecule produced by the liver, then transported to the membranes of animal cells. Cholesterol, which is found embedded in the plasma membrane of animal cells alongside other molecules like phospholipids, plays a vital role there.
The cholesterol of animal cell membranes help increase the fluidity of the membrane and also helps prevent the membrane from freezing during low temperatures.