Tongue- This organ is a mass of interwoven, striated muscle tissue, interspersed with glands and fat and covered with a mucous membrane. Stained with Mallory trichrome stain, which contains three components- aniline blue, acid fuchsin, and orange G. As striated muscle, human tongue muscle usually stains red, due to the orange G component of stain.
The tongue is divided in to dorsal and ventral surface. The dorsal surface is a stratified squamous keratinized epithelium which is characterized by numerous mucosal projections called papillae. The ventral surface is stratified squamous non-keratinized epithelium which is smooth.
Tongue section- showing lingual papillae, taste buds, striated muscles, gustatory pore.
The top surface bears numerous projections of the mucous membrane, called papillae, which contain taste buds.
Oral Part exhibit lingual papillae of the various types
Filiform papillae- Most numerous, appears short conical projections that give rise to velvety appearance of the tongue, but they are not involved in taste sensation.
Fungiform papillae- Rounded reddish elevations with high vascular connective tissue core, with narrow base and broad top. each bears a few taste buds
Vallate papillae- broad circular top and narrow base. Lined by stratified squamous non-keratinized epithelium. Base of each papillae contains circular and longitudinal muscle fibers.
Foliate papillae- leaf like Rudimentary in humans. It is functional in lower animals
Taste buds- Made up of modified epithelial cells. Each bud has cavity which opens on the surface through gustatory pore.