The nose is an important part of the respiratory system. It has several functions, including:

• Allowing air to enter the body: The nose is the main gate to the respiratory system, allowing air to enter the body.
• Filtering and cleaning air: The nose filters and cleans air to remove particles and allergens. The respiratory region of the nasal cavity functions to humidify, warm, filter, protect, and eliminate debris.
• Warming and moistening air: The nose warms and moistens air so it can move comfortably into the respiratory system.
• Providing a sense of smell: The nose contains nerve cells that communicate with the brain to provide a sense of smell.
• Contributing to facial appearance and sound: The nose is a prominent aspect of facial appearance and contributes to how a person sounds when they speak.

The nasal cavity is the most cephalic part of the respiratory tract and is divided into two separate cavities by the septum. Each cavity consists of a roof, floor, medial wall, and lateral wall. Within each cavity are three regions: nasal vestibule, respiratory region, and olfactory region. The respiratory region is covered in respiratory epithelium and mucous cells, and it is the most substantial part of the nasal cavity. The nasal cavity has an abundant supply of vasculature to aid in functions of warming and humidifying inhaled air.