terpene

thumb|upright|Many terpenes are derived commercially from conifer resins, such as those made by this pine.

Terpenes ( ) are a large and diverse class of natural products with the general formula , where n ≥ 2. They serve as crucial biosynthetic building blocks in many organisms, particularly plants. Comprising more than 30,000 compounds, these unsaturated hydrocarbons are produced predominantly by plants, particularly conifers. In plants, terpenes and terpenoids are important mediators of ecological interactions, while some insects use some terpenes as a form of defense. Other functions of terpenoids include cell growth modulation and plant elongation, light harvesting and photoprotection, and membrane permeability and fluidity control.