Submerged plants are aquatic plants that grow entirely underwater. They play a crucial role in aquatic ecosystems by providing habitat and food for various organisms, including fish and invertebrates. These plants can be found in freshwater and saltwater environments, and they help improve water quality by absorbing nutrients and producing oxygen through photosynthesis. Common examples of submerged plants include eelgrass, hornwort, and waterweed. They can vary in size and shape, with some having long, slender leaves while others may be more bushy. Submerged plants also help stabilize sediments, reducing erosion and promoting a healthy aquatic environment.