What role do steroids serve in the body?

Steroids play a significant role as components of cell membranes. They contribute to membrane fluidity and stability. In particular, cholesterol, a type of steroid, is an essential component of the phospholipid bilayer that makes up cell membranes. Cholesterol helps to maintain the integrity and functionality of the membrane, allowing it to remain flexible and move while also providing protection and control over the passage of substances in and out of the cell.

This unique characteristic of steroids in cell membranes distinguishes them from other roles listed in the other options presented. For example, while energy sources for cellular processes are primarily carbohydrates and fats, steroids are not utilized in the same way. Steroids also do not serve as precursor molecules for amino acids nor do they function as storage for genetic information; these functions are instead related to proteins and nucleic acids, respectively. Understanding the specific functions of steroids is crucial in comprehending their integral role in biological systems.