Plant resin
Plant resin is a sticky mixture of compounds produced by many plants, especially conifers. It can seal wounds and deter herbivores and pathogens.
Resin duct: A secretory canal in plant tissue that stores and transports resin. These canals carry resin toward wounds in many conifers.
Monoterpene: A terpene built from two isoprene units, commonly found in plant essential oils. Volatile monoterpenes give fresh resin much of its characteristic odor.
Conifer: A cone-bearing seed plant, such as a pine, fir, or spruce. Conifers are prominent resin producers and include many familiar resin-bearing trees.
Rosin: The solid residue left after volatile components are distilled from crude oleoresin. Rosin is a processed resin product used in adhesives, inks, and instrument bowing.
Gum: A water-soluble or water-swellable plant exudate made largely of polysaccharides. Unlike resin, gum generally dissolves or swells in water rather than consisting mainly of hydrophobic compounds.
Terpene: A diverse class of compounds built from five-carbon isoprene units, including many volatile plant chemicals. Many resin volatiles are terpenes that repel insects or attract their enemies.
Diterpene: A terpene built from four isoprene units, often found in plant resins. Diterpenes include resin acids that remain after volatile compounds evaporate.
Angiosperm: A flowering plant whose seeds develop inside an ovary that typically becomes a fruit. Some flowering plants also make resin, showing that resin production is not confined to conifers.
Turpentine: A volatile solvent distilled from oleoresin, especially from pine trees. Distillation separates this resin-derived liquid from solid rosin.
Latex: A milky fluid of suspended particles produced by specialized secretory cells in some plants. Latex is a distinct plant secretion, even when it also functions in defense.