Operculum
A)a deep sea fish with a skeleton of cartilage
B)a flap covering the gills of a bony fish
C)an organ along the side of a fish that can detect movement in the water
D)scales that resemble a tooth, having a broad base and a narrow pointed top
E)an organ for breathing underwater, consisting of membranes through which oxygen can pass
B) a flap covering the gills of a bony fish.
The correct answer is B) a flap covering the gills of a bony fish.
An operculum is a structure found in bony fish that covers and protects the gills. It is a flexible bony flap that opens and closes to allow water to flow over the gills, which enables the fish to extract oxygen from the water for respiration. The operculum helps regulate the movement of water and prevents debris from entering the gills, ensuring efficient respiration for the fish.