| Submerged hydrophytes show |
| a) | stomata | b) | Abundant air sacs |
| c) | Well developed mechanical tissue | d) | Secondary growth |
| (b)The plants, which live in abundance of water are called hydrophytes. The hydrophytic plants, which remain under water are called submerged hydrophytes. The air spaces are extensively developed in root, stem and leaves of these plants.e.g., Hydrilla, Vallisneria, Ceratophyllum, Utricularia, etc. |