Four Characteristics of Seed Plants

Increased Chance of Reproduction

• "The seed includes three primary regions: the embryo, nutritive tissue, and seed coat," according to the University of California. The seed coat protects the inner reproductive structures from the outside environment, such as the freezing temperatures of winter. Inside the seed, the embryo is surrounded by ample food sources that will support rooting and the growth of the plant's first leaves. A spore must chance itself against the environment and for finding adequate food sources for development, while a seed does not.

Gymnosperms And Angiosperms

• Gymnosperms such as the pine tree rely on wind pollination to develop seed while angiosperms such as flowers have formed a symbiotic relationship with pollinator species such as bees and hummingbirds. According to Peter Raven in the "Biology of Plants," "Gymnosperms are overwhelmingly the most successful vascular plants at the present time."

Secondary Growth

• According to the University of California, "Secondary growth is the increase in diameter of existing tissues and organs, and this process results in secondary tissues." Secondary growth occurs only in seed plants, allowing for the impressive height of the trees that exist today, for example. The secondary tissues that form are called wood and periderm. Inside a seed plant, wood is simply an accumulation of xylem, a tissue which is used to transport minerals and water from the roots. The other secondary structure known as cork functions to replace old surface cells as the plant expands. This is seen as bark on the outside of a tree.

Longevity

• Due to the various advantages of seed plants over non-seed plants such as the reproductive structure of the seed, wind and animal pollination, and secondary growth, it's possible for seed plants to survive much longer than non-seed plants. This is necessary for survival because seed reproduction limits the distance at which a plant can expand. Non-seed plants can reproduce over a much larger area than seed plants because of the greater distances that spores can travel.