What are the external openings of the nasal cavities commonly referred to as?

The external openings of the nasal cavities are commonly referred to as external nares. This term specifically describes the two nostrils that allow air to enter and exit the nasal passages. The external nares play a crucial role in the respiratory system, as they are the first point of contact for inhaled air, allowing it to be filtered, warmed, and humidified before reaching the lungs.

Understanding this term is essential for studying the anatomy of the respiratory system, as it helps to differentiate between the various structures involved in respiration. The other options represent different components related to the nasal passages and airways: nasal passages are the channels within the nose, sinuses are air-filled spaces surrounding the nasal cavity, and turbinates are bony structures within the nasal passage that help with airflow and filtration. While all these components contribute to the functioning of the nasal cavities, it is the external nares that specifically refer to the openings themselves.