cholesterol

Cholesterol is a polycyclic ring compound that is predominately hydrocarbon and therefore hydrophobic. It is important in the metabolism of eucaryotic cells because it

• is a component of cell membranes and involved in membrane fluidity

• is a precursor to many steroid hormones

When cholesterol is incorporated into a plasma membrane it does so with a specific polarity. The hydroxyl group of the cholesterol is oriented in the membrane such that it interacts with the water in the inside of the cell or the water on the outside of the cell.