Answer
Both seedless vascular plants and nonvascular plants have swimming sperm, requiring that they have a film of water through which these sperm can swim at the appropriate time during the lifecycle. They differ in the seedless vascular plants having strong vascular tissue, allowing them to grow much larger than nonvascular plants, and having true roots and true leaves for better nutrient extraction from soil and more effective photosynthesis.
Work Step by Step
Review Concepts 29.2 and 29.3, making lists of major features for both groups of plants in the question. Then, simply compare the list, highlighting the shared features and those which are obviously very different between the groups.