Yam (vegetable) Yam (vegetable) Yam is the common name for some plant species in the genus "Dioscorea" (family Dioscoreaceae) that form edible tubers. Yams are perennial herbaceous vines cultivated for the consumption of their starchy tubers in many temperate and tropical world regions. The tubers themselves are also called "yams", having numerous cultivars and related species. In parts of the United States and Canada, "yam" is sometimes used to refer to varieties of the unrelated sweet potato ("Ipomoea batatas"). The name, yam, appears to derive from Portuguese "inhame" or Canarian (Spain) "ñame", which derived from West African languages during trade. The main
Morphism of algebraic varieties by taking the pre-images of prime ideals. All morphisms between affine schemes are of this type and gluing such morphisms gives a morphism of schemes in general. Now, if "X", "Y" are affine varieties; i.e., "A", "B" are integral domains that are finitely generated algebras over an algebraically closed field "k", then, working with only the closed points, the above coincides with the definition given at #Definition. (Proof: If is a morphism, then, writing formula_22, we need to show where formula_24 are the maximal ideals corresponding to the points "x" and "f"("x"); i.e., formula_25. This is immediate.) This fact means