Give reasons. a. Aquatic plants have air spaces in their body​

Many water plants develop large internal air spaces—aerenchymatous tissues—in their roots and shoots. These air spaces make the tissues buoyant and help them float. ... If the plant grows or floats to the surface, oxygen can also easily diffuse down through the air spaces

Explanation:

The air spaces between the plant cells, makes them buoyant and easy to float on water. The buoyancy keeps plants upright or floating in the water. These air spaces occur within stems, leaves and roots, and frequently link up to form a continuous passage for the circulation of oxygen to all parts of the plant.

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