Which structure protects the gills in many fish?

Which structure protects the gills in many fish?

• A. Operculum.
• B. Dorsal fin.
• C. Anal fin.
• D. Caudal fin.

Answer: (A)

Protecting the gills in many fish is accomplished by the operculum, a gill cover. It’s a bony plate that sits over the gill arches, shielding the delicate gill filaments from damage and debris. When the fish opens its mouth and closes the operculum, water is drawn in and flows over the gills, enabling gas exchange. The dorsal fin, anal fin, and caudal fin serve mainly for stability, steering, and propulsion, not for protecting or covering the gills.