[Embryogenesis of the human tongue].

Abstract

Developmental peculiarities of the tongue as a whole and its main structural elements (muscles, membranes, glands, lingual tonsil) have been studied in 120 human embryos and fetuses 5-week-old--9-month-old. Transmissive electron microscopy, electron histochemistry (for estimation of 5'-nucleotidase activity), staining of semithin slices with toluidine blue and aniline++ pink have been applied. Problems on migration of myogenic elements in the developing tongue have been discussed. Ultrastructure of gustatory bulbs of the human fetus tongues has been investigated. A complete formation of the tongue takes place by the 8th-9th months of the prenatal development.