Final answer:
The sinuses connected at the confluence are the frontal, maxillary, sphenoidal, and ethmoidal sinuses; they serve several respiratory functions and are in the skull bones associated with their names.
Step-by-step explanation:
The sinuses that connect at the confluence of sinuses are the frontal sinus, maxillary sinus, sphenoidal sinus, and ethmoidal sinus. These sinuses are air-filled cavities located within the bones of the skull that help to warm, humidify incoming air, produce mucus to trap particles, and lighten the weight of the skull while adding resonance to the voice. The frontal sinus is situated above the eyebrows in the frontal bone, the maxillary sinuses below the orbits in the maxillary bones, the sphenoid sinus within the body of the sphenoid bone, and the ethmoid air cells located in the ethmoid bone.
These sinuses are named for their respective skull bones and are connected to the nasal cavity. When air passes through the nasal cavity, it is filtered and moistened by the mucus and mucosa lining the sinuses and nasal conchae, thus aiding in respiratory health. The largest of these is the maxillary sinus, which is typically involved during sinus infections due to its position and the nature of its drainage.