The shape of turbinate is gradientlly changed from anterior to posterior. These structure decrease Reynold share stress. Heat and vapor exchange work effectively. This is parasympathetic nerve dominant state. Treated view is assumed as a nasal cavity at athletic.
Oxygen demand is high, and respiratory flow is rapid.
Adrenaline release occurs, and turbinate size gets small. The resistance of nasal cavity get decreased. The depth of flow is long. Oxygen demand is prior to heat and vapor exchange. This is sympathetic nerve dominant state.