What is the function of respiratory epithelium and superficial blood vessels in nasal cavity?

Respiratory epithelium:

- Olfactory function: The respiratory epithelium contains specialized olfactory cells that detect and transmit

odours to the brain.

- Protection: The epithelium acts as a physical barrier, preventing the entry of foreign particles, pathogens, and allergens into the respiratory tract.

- Mucous production: The epithelium secretes mucus, which traps inhaled particles and helps humidify the air.

- Cilia movement: The cilia lining the epithelium beat synchronously, propelling mucus and trapped particles towards the throat to be swallowed or expelled.

- Immune response: The epithelium contains immune cells that help detect and respond to infections and allergens, triggering appropriate immune responses.

Superficial blood vessels:

- Vasodilation and vasoconstriction: The superficial blood vessels in the nasal cavity undergo dilation (widening) and constriction (narrowing) to regulate airflow and blood flow.

- Heat exchange: The extensive network of blood vessels helps warm the inhaled air, reducing irritation to the lower respiratory tract.

- Humidification: The moisture released from the blood vessels helps humidify the air, preventing drying of the respiratory mucosa.

- Sneezing reflex: When the blood vessels become congested or irritated, they can stimulate the trigeminal nerve, triggering the sneezing reflex to expel foreign substances.

- Nosebleeds: The superficial location of blood vessels makes the nasal cavity susceptible to nosebleeds, especially with trauma or inflammation.