Gross Anatomy and Histology of the Tongue

Gross Anatomy of the Tongue

• The tongue is a highly mobile, muscular organ located in the floor of the mouth.
• It is essential for mastication, deglutition, and speech.
• The superior surface of the tongue is covered by a mucous membrane containing numerous papillae.
• Papillae types include filiform, fungiform, circumvallate, and foliate, contributing to texture and taste perception.
• The tongue is anchored to the hyoid bone, mandible, and styloid processes by muscles.
• Intrinsic muscles alter tongue shape, while extrinsic muscles move the tongue within the oral cavity.
• Intrinsic muscles facilitate subtle tongue movements for speech and swallowing.

Histology of the Tongue

• The tongue is composed of skeletal muscle fibers bundled for movement.
• The surface epithelium is stratified squamous non-keratinized, protecting against abrasion.
• The lamina propria, underlying the epithelium, contains connective tissue, blood vessels, and nerves.
• Taste buds are found in certain papillae (circumvallate, foliate, and some fungiform papillae) enabling taste sensation.
• Taste cells, specialized epithelial cells within the taste buds, respond to taste stimuli.
• Cranial nerves provide sensory innervation to the tongue.

Lingual Papillae

• Filiform papillae are numerous, thin, thread-like projections covering most of the tongue's surface.
• Filiform papillae are responsible for the tongue's rough texture and tactile sense.
• Fungiform papillae are mushroom-shaped, interspersed among filiform papillae, and contain taste buds.
• Circumvallate papillae are large, rounded papillae in a V-shaped row at the posterior tongue, containing numerous taste buds.
• Foliate papillae are located on the tongue's lateral margins, also containing taste buds.

Lingual Nerves and Blood Supply

• The tongue receives sensory innervation from the trigeminal nerve (V3) for general sensation (pain, touch) on the anterior two-thirds.
• The glossopharyngeal (IX) nerve innervates the posterior one-third of the tongue.
• The vagus nerve (X) is also involved in tongue innervation.
• The glossopharyngeal nerve carries taste sensations from the posterior one-third.
• The lingual artery supplies the primary blood supply to the tongue, branching to various regions.
• Venous drainage parallels the arteries, removing blood from the tongue.

Muscles of the Tongue

• Intrinsic tongue muscles change the tongue's shape.
• Extrinsic tongue muscles move the tongue in the oral cavity.
• These muscles are essential for speech, mastication, and swallowing.

Tongue and Clinical Implications

• Anatomical or functional issues with the tongue can indicate medical problems.
• Changes in appearance, size, or texture can signify underlying concerns.
• Oral cancer can appear as lesions or irregularities on the tongue.
• Dysphagia (difficulty swallowing) or speech impairments can arise from tongue disorders.
• Medications and systemic diseases can also impact tongue structure and function.
• A thorough assessment of the tongue (appearance, texture, responsiveness to touch and taste) is essential in clinical evaluation.

Explore the intricate structure and function of the tongue in this quiz. Understand its muscular composition, the roles of different papillae, and the significance of intrinsic and extrinsic muscles. This quiz emphasizes the relationship between anatomy and physiological functions such as taste, speech, and swallowing.