Final answer:
The three parts of the ethmoid bone are the perpendicular plate, which forms the upper part of the nasal septum; the cribriform plates, for olfactory transmission and constituting the nasal cavity roof; and the lateral masses, including the superior and middle nasal conchae, which are involved in airflow and contain the ethmoid air cells.
Step-by-step explanation:
The ethmoid bone is an intricate part of the human skull, comprising of three main parts that play vital roles in the structure and functionality of the nasal region and its adjoining areas. The three parts of the ethmoid bone include:
- The perpendicular plate, which forms the upper portion of the nasal septum, providing separation of the left and right airways in the nose.
- The cribriform plates, which sit at the roof of the nasal cavity and also contribute to the floor of the anterior cranial fossa; they contain small holes through which olfactory fibers pass from the nasal cavity to the brain.
- The lateral masses, that consist of the superior and middle nasal conchae—these are curvy projections that extend into the nasal cavity from the lateral walls and are integral to the airflow and filtration in the nasal passages. The lateral masses also contain the ethmoid air cells, which are part of the paranasal sinus system.
These structures are crucial for supporting the nasal cavity, contributing to the structure of the orbits, and facilitating olfactory functions.