Lingual Papillae & Taste Bud Histology
Lingual papillae of the Tongue
Lingual papillae cover 2/3rds of its anterior surface; lingual tonsils cover its posterior surface.
There are three types of lingual papillae:
- Filiform, fungiform, and circumvallate; a 4th type, called foliate papillae, are rudimentary in humans.
- Surface comprises stratified squamous epithelia
- Core comprises lamina propria (connective tissue and vasculature)
- Skeletal muscle lies deep to submucosa; skeletal muscle fibers run in multiple directions, allowing the tongue to move freely.
- Taste buds lie within furrows or clefts between papillae; each taste bud comprises precursor, immature, and mature taste receptor cells and opens to the furrow via a taste pore.
Distinguishing Features:
Filiform papillae
- Most numerous papillae
- Their role is to provide a rough surface that aids in chewing via their keratinized, stratified squamous epithelia, which forms characteristic spikes.
- They do not have taste buds.
- "Fungi" refers to its rounded, mushroom-like surface, which is covered by stratified squamous epithelium.
- Are also rounded, but much larger and more bulbous.
- On either side of the circumvallate papillae are wide clefts, aka, furrows or trenches; though not visible in our sample, serous Ebner's glands open into these spaces.
Images:
Histology (Mark Braun, MD, & Indiana University: http://medsci.indiana.edu/c602web/602/c602web/toc.htm; http://www.indiana.edu/~anat215/virtualscope2/start.htm)