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Over time, seed plants have evolved in a variety of ways and acquired a variety of adaption mechanisms to cope with the altered environment. Seed plants, in general, require water to reproduce.

Seeds and pollen are used to differentiate seed plants from seedless vascular plants. These novel structures allowed seed plants to conquer dry land by reducing or eliminating their reliance on water for gamete fertilization and embryo development.

• The reproductive component of the plant body is the flower.
• The ovary develops into a fruit after fertilization.
• A diploid plant body matures in the sporophyte phase and finally generates spores through meiosis. These spores divide mitotically to generate gametophytes, gamete-producing organisms.

The sperm (gametes) of the plant are contained in pollen grains, which are male gametophytes. Desiccation (drying out) and mechanical damage are avoided by encasing the tiny haploid (1n) cells in a protective covering. Pollen grains can transfer the plant's gametes far from their originating sporophyte.

• Pollen grains are dispersed by wind, water, or pollinators.
• Desiccation is prevented throughout the structure, and the female organs can be reached without the need for water.