On which types of fishes are the gills covered with operculum? a) Bony fish b) Cartilaginous fish c) Both (a) and (b) d) neither (a) nor (b)
option A .. The operculum is a bony flap covering the gills in bony fishes. It regulates the direction of water flow over the gills. It is not found in cartilage fishes. Whereas scales, gill slits and pelvic fins are found in both the fishes, bony and cartilaginous.
