Trichome
A trichome is a hairlike outgrowth from a plant’s epidermis. Trichomes can deter herbivores, reduce water loss, or secrete substances.
Plant epidermis: The outermost cell layer covering a plant’s leaves, stems, roots, and other organs. Trichomes arise from specialized cells in this outer layer.
Plant defense against herbivores: The physical and chemical strategies plants use to reduce damage by animals that eat them. Trichomes are one of the plant’s surface defenses against feeding.
Cotton fiber: A long, single-celled seed hair produced by cotton plants and harvested as textile fiber. It is a specialized trichome whose elongated growth has major agricultural value.
Plant spine: A sharp, pointed plant structure that deters animals and may develop from a leaf or stipule. Spines are rigid defensive organs rather than epidermal hairlike outgrowths.
Plant cell differentiation: The process by which plant cells acquire distinct structures and functions. Trichome development begins when epidermal cells adopt a specialized identity.
Glandular trichome: A trichome with secretory cells that release substances such as oils, resins, or mucilage. Its secretions can repel, poison, trap, or otherwise affect herbivores.
Cannabis trichome: A glandular surface structure on cannabis that produces resin containing cannabinoids and terpenes. Its resin production shapes the plant’s chemical profile and commercial uses.
Plant prickle: A sharp epidermal projection, such as those found on rose stems, that lacks vascular tissue. Like trichomes, prickles arise at the surface, but they are larger and structurally distinct.
Arabidopsis thaliana: A small flowering plant widely used as a model organism in biological research. Its leaf trichomes enabled genetic studies of cell fate and branching.
Non-glandular trichome: A trichome that lacks specialized secretory cells and primarily serves structural functions. Its hairs can obstruct insect movement or feeding without producing secretions.