Artemisia annua: A plant species of the genus ARTEMISIA, family ASTERACEAE. It is the source of the antimalarial artemisinin (ANTIMALARIALS).Artemisia: A plant genus of the family ASTERACEAE with strong-smelling foliage. It is a source of SANTONIN and other cytotoxic TERPENES.Artemisinins: A group of SESQUITERPENES and their analogs that contain a peroxide group (PEROXIDES) within an oxepin ring (OXEPINS).Artemisia absinthium: A plant species of the genus ARTEMISIA, family ASTERACEAE that has been used in ABSINTHE. The oil contains neurotoxic 1-thujone and d-isothujone.Chenopodium: A plant genus in the CHENOPODIACEAE family.Foeniculum: A plant genus of the family APIACEAE used in SPICES.SesquiterpenesTrichomes: Hair-like extensions on specialized epidermal surfaces of plants which protect against damage from insects, animals, light degradation and fungal infection. Trichomes may also occur on certain unicellular EUKARYOTES.Antimalarials: Agents used in the treatment of malaria. They are usually classified on the basis of their action against plasmodia at different stages in their life cycle in the human. (From AMA, Drug Evaluations Annual, 1992, p1585)Plant Extracts: Concentrated pharmaceutical preparations of plants obtained by removing active constituents with a suitable solvent, which is evaporated away, and adjusting the residue to a prescribed standard.Plant Leaves: Expanded structures, usually green, of vascular plants, characteristically consisting of a bladelike expansion attached to a stem, and functioning as the principal organ of photosynthesis and transpiration. (American Heritage Dictionary, 2d ed)Euphorbiaceae: The spurge family of flowering plants, in the order Euphorbiales, contains some 7,500 species in 275 genera. The family consists of annual and perennial herbs and woody shrubs or trees.