Question

how does carbon dioxide diffuse in submerged aquatic plants

Answer 1

Since it's harder to diffuse carbon dioxide in water, some aquatic plants float on the water's surface or have a few leaves sticking out of the water. These leaves have stomata and collect carbon dioxide, like terrestrial plants. Other aquatic plants are completelysubmerged.

Answer 2

co2 can be dissolved in water.
over the last 200 years oceans have absorbed 50%of co2 absorbed emitted by human activities..