What divides each nasal cavity into several divisions?

The correct answer is that turbinates are responsible for dividing each nasal cavity into several divisions. Turbinates, also known as nasal conchae, are bony structures covered in mucous membranes that extend into the nasal cavity. They help to increase the surface area for filtering, warming, and humidifying the air we breathe. By creating distinct air passages, turbinates enhance airflow regulation and contribute to the overall respiratory process.

While the septum indeed separates the left and right nasal cavities, it does not create divisions within each cavity. Sinuses refer to the air-filled spaces located within the bones of the skull that connect with the nasal cavity but do not divide the cavity itself. Conchae is often used interchangeably with turbinates, but the specific mention of turbinates emphasizes their unique role in the divisions of the nasal cavity more accurately.