frøplantene

Frøplantene, also known as Spermatophytes, represent the most dominant and widespread group of plants on Earth today. They are characterized by their ability to produce seeds, which is a significant evolutionary advancement. Seeds provide protection and nourishment for the developing embryo, allowing for dispersal to new environments and survival through unfavorable conditions. This reproductive strategy has contributed greatly to their ecological success.

The life cycle of frøplantene involves alternation of generations, with a prominent sporophyte generation. The sporophyte produces two types of spores: microspores, which develop into pollen grains containing the male gametophyte, and megaspores, which develop within ovules and contain the female gametophyte. Fertilization occurs when a pollen grain reaches an ovule, leading to the formation of a zygote that develops into an embryo within the seed.

Frøplantene are broadly divided into two main groups: gymnosperms and angiosperms. Gymnosperms, meaning "naked seeds," include conifers, cycads, ginkgoes, and gnetophytes. Their seeds are typically borne on the surface of cone scales or similar structures, without being enclosed within a fruit. Angiosperms, or flowering plants, are characterized by the presence of flowers and fruits, which enclose the seeds. This group is the most diverse and includes a vast array of plants from grasses and trees to herbs and shrubs, playing a crucial role in ecosystems and human agriculture.