Facts on Seed Plants

History

• Fossils have shown that seed plants existed almost 350 million years ago, in the Devonian age. Records show both seed plants and fern-like plants growing at the same time (see Resources).

Gymnosperms

• Gymnosperm seed plants have "naked," or exposed, seeds. Ginkgo trees, pine trees and other conifers are examples of gymnosperms.

Angiosperms

• Flowers and other plants that produce fruit are angiosperms. The seeds have a protective coating, an embryo and a food supply. Corn, roses and apple trees are examples of angiosperms.

Pollination

• Angiosperms are plants pollinated by insects and animals. Some plants are self-pollinating. Gymnosperm are seed plants pollinated by the wind.

Reproduction

• Gymnosperm plants have wing-shaped pollen that can fly to the female plants to pollinate them. Angiosperm plants have a stamen where pollen is produced and a stigma where the pollen is deposited to produce seeds.

Soil Conditions

• Seed plants require moisture to grow but not to reproduce, since their pollen is dry. Other plants, like ferns and mosses, still require water to generate pollination.