Why do plants have tendrils?

Why do aquatic plants need land plants?

• I have a science homework question... Why do aquatic plants in a stream need land plants? How do they relate? Our hints about this question so far are: -Stream ecosystems are not ok without land plants, but land plants can be ok without streams. Help pleaseeee? :)

• Answer:

  Streams receive water runoff from the land. This runoff brings in a constant source of detritus and soil. The dissolved nutrients available to aquatic plants come from decaying detritus. This creates a detritus based food web in the stream.The source of the detritus is the plants growing along the riparian zone and the general watershed that feeds into the stream.