👉 Pinnulae are small, oval-shaped structures found on the surface of many aquatic animals. These structures are often associated with the digestive process in aquatic animals and are responsible for the breakdown of food into smaller particles that can be absorbed by the animal's digestive system. In aquatic ecosystems, pinnulae can also play a role in water movement and nutrient cycling. They help to distribute nutrients throughout the water column, which is essential for the growth and survival of aquatic organisms. Pinnulae
