Nose, olfactory region and the sinuses (L1) 2012

Nose Olfactory mucosa Respiratory mucosa nasal conchae Nose wings

Nasal ala lamina propria hyaline cartilage mixed glands hair skeletal muscle unkertinized stratified epithelium Skin -OUTSIDE

Respiratory mucosa of nasal cavity Ciliated pseudostratified cylindrical epithelium Mucous goblet cells artery mixed glands large veins bone

Olfactory region Located in respiratory part of the nasal cavity Begins at the front of the anterior end of the superior concha and extends posterior for about 1 cm Extends laterally from the roof over the largest part of the superior concha and medially for about 1 cm over the nasal septum

Olfactory mucosa OLFACTORY EPITHELIUM LAMINA PROPRIA Olfactory nerve fibers Large veins Gland of Bowman LAMINA PROPRIA bone

Olfactory epithelium Cell types Pseudostratified cylindrical epithelium Olfactory cells Support cells Basal cells Olfactory cilia Olfactory vesicle dendrite Support cell Olfactory cell body Basal cell axon

Structure and function Cell type Structure and function Pseudostratified cylindrical epithelium Ciliated (about 300 cilia on apical surface) Mucus transport Olfactory cells Bipolar neurons, at apex 6-8 cilia Very long non motile Smell, generates action potential transmits impulse Support cells Broad cilindrical apexs with narrow bases Microvilli are submerge in fluid layer Well developed junctional complexes Basal cells Small, lie on basal lamina Do not extend to surface Generative stem cells

Lamina propria Contains many veins - usually flat (Allergies - veins fill with blood and cause a blocked nose) Contains tubulo-alveolar glands namely Bowman’s glands that secrete a thin watery substance that facilitates smell stimuli Rest of the lamina propria contains mixed glands The lamina propria is located against the perichondrium of the hyaline cartilage

Paranasal sinuses Mucosa Epithelium: Pseudostratified cylindrical with cilia Thinner than nasal epithelium Less goblet cells and mixed glands Thinner basement membrane Lamina propria is thin and rests against the periosteum of the bone