CAMRT Radiography Practice Exam

Which bone contains three main groups of sinuses?

1. Frontal Bone

2. Maxilla

3. Ethmoid Bone

4. Sphenoid Bone

The correct answer is: Ethmoid Bone

The ethmoid bone is recognized for containing three main groups of sinuses known as the ethmoidal air cells. These sinuses are found within the lateral masses of the ethmoid bone and are categorized into anterior, middle, and posterior ethmoidal air cells. These air-filled spaces play a crucial role in lightening the weight of the skull, humidifying and warming inhaled air, and contributing to vocal resonance. The frontal bone also contains sinuses known as the frontal sinuses, while the maxilla has maxillary sinuses. The sphenoid bone contains the sphenoidal sinuses. However, the ethmoid bone is distinctive because it houses multiple sinus groups within its structure, making it the correct answer to the question. Each group of ethmoidal air cells has its own drainage pathways into the nasal cavity, further illustrating the complexity and importance of the ethmoid bone in cranial anatomy.