Plántula de Cornus
In Botany, more specifically in spermatophytes, seedling is called the stage of development of the sporophyte that begins when the seed breaks dormancy and germinates, and ends when the sporophyte develops its first non-cotyledonary leaves mature, ie functional. A typical seedling can be divided into the primary root that derives from the radicle of the embryo, and the primary stem that consists of the primary stem with one or more cotyledons or embryonic leaves (present in the seed, which depending on the species will develop during the stage seedling to be large and functional as photosynthetic, or not), if there are two cotyledons these appear to be at the same height of the stem, in the first "knot" or knot cotiledonar; The stem between the cotyledons and the root is called hypocotyl ("under the cotyledons"), the stem above the cotyledons until the first non-cotyledon leaf is the epicotyl ("over the cotyledons"). The transition from stem to root may not be visible externally to the naked eye (morphologically), but its anatomical identity is maintained and it is in the wake of each where they can be differentiated. Bibliography
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