LARYNX

Function: the passageway for the air between the oropharynx and trachea, organ for speech (phonation)

Composition:

• Ciliated pseudostratified columnar epithelium with basement membrane

Cells:

• Ciliated cells - the most numerous of the cell types, extend through the full thickness of the epithelium

• Mucus (goblet) cells - are interspersed among the ciliated cells and also extend through the full thickness of the epithelium

• Brush cells -columnar cells that bear microvilli. The basal surface is in synaptic contact with the afferent nerve endings that penetrate the basal lamina and form trigeminal nerve

• Small granule cells - their cytoplasm processes is sometimes observed extending to the lumen and cytoplasm contains numerous, membrane-bonded, dense-core granules

• Basal cells

• Lamina propria

Function: conditioning (warming, moistening and removal of particulate materials) of the air, prevention the epithelium from dehydration by moving air

Composition: loose connective tissue with rich vascular network - capillary loops, muco-serous glands

• Irregularly shaped plates of hyaline and elastic cartilage

VOCAL FOLDS (CORDS)

Location: two folds of mucosa that project into the lumen

Function: control the flow of air and vibrate to produce sound

Composition:

• Nonkeratinized stratified squamous epithelium
• Loose connective tissue with muco-serous glands
• Supporting ligament
• Vocalis muscles - striated skeletal muscles
• Plates of hyaline and elastic cartilage

FALSE VOCAL CORDS (VENTRICULAR FOLDS)

Location: two folds of mucosa that just above the vocal folds in elongated recess of larynx called ventricle

Function: are important in creating sound resonance

Composition:

• Nonkeratinized stratified squamous epithelium
• Loose connective tissue with muco-serous glands
• Supporting ligament
• Plates of hyaline and elastic cartilage