Question

Human hormones testosterone and estrogen are considered lipids. What could be the reason for this?

Answer 1

Testosterone and estrogen are steroid hormones. The hormone part of the name refers to their biological function.

Explanation:

Testosterone and estrogen are derived from cholesterol which is a sterol lipid.
Hence they are lipids. Like all lipids they are fatty chain molecules that are insoluble in water and soluble in non polar solvents.
Steroids have a basic carbon structure with four fused rings. The different functional groups attached to the rings make them different from each other.
http://www.newworldencyclopedia.org/entry/Testosterone