Providing examples, explain how sexual reproduction in plants has evolved to become less dependent on water

Question

anonymous · Answer

Pollen. 

The nonvascular plants and even a few vascular plants (e.g. ferns) reproduce by having the sperm swim through the external environment. This swimming requires a water film in the external environment, and also requires that the ovum be in a structure close enough to the ground that the sperm can swim to it. 

Gymnosperms and angiosperms make pollen. Sperm are confined within a pollen grain. No swimming is required.