An example of an amphipathic molecule found in living cells is what?

An amphipathic molecule is characterized by having both hydrophilic (water-attracting) and hydrophobic (water-repelling) regions within the same molecule. This structural property is crucial for forming biological membranes, particularly the lipid bilayer of cell membranes. Phospholipids are a classic example of this type of molecule; they have a hydrophilic "head" that is attracted to water and two hydrophobic "tails" that repel water.

In living cells, phospholipids play a vital role in the formation of cellular membranes due to their ability to spontaneously organize into bilayers. This arrangement allows the hydrophilic heads to face the aqueous environment both inside and outside the cell, while the hydrophobic tails face inward, away from the water. This unique structure is essential for maintaining the integrity and functionality of the cell membrane, allowing it to act as a barrier while also facilitating the transport of substances in and out of the cell.

Cholesterol, although it is an important component of cellular membranes, is primarily hydrophobic with a small hydrophilic hydroxyl group. Triglycerides consist of glycerol and three fatty acids, which are largely hydrophobic and do not have a significant hydrophilic region.