Main Features of Angiosperms

Angiosperms or flowering plants are the most advanced, most diverse and most dominant group of land plants. They are seed-producing plants and can be distinguished from the gymnosperms by a series of derived characteristics such as flowers, endosperm within the seeds, and the production of fruits that contain the seeds. They have developed from Gymnosperms over the period and replaced them as most dominant group of plants some 100 million years ago.

Main Features of Angiosperms

Benefit of Flowers

Due to Flowers, Angiosperms were able to adapt a wider range of ecological niches, making them largely dominate terrestrial ecosystems.

Reduced Male and Female Parts

Instead of cones in Gymnosperms, the Angiosperms have stamens, reduced male parts and an enclosed ovule. The Stamens are much lighter than the corresponding organs of gymnosperms and have contributed to the diversification of angiosperms through time with adaptations to specialized pollination methods. In some advanced species, the Stamens were modified to prevent self-fertilization, enabling further diversification.

Dominant Sporophyte

The main plant of Angiosperms is a Diploid Sporophyte which is divided into roots, stems and leaves. The male gametophyte in angiosperms is significantly reduced in size compared to those of gymnosperm seed plants. The smaller pollen decreases the time from pollination — the pollen grain reaching the female plant — to fertilization of the ovary; in gymnosperms, fertilization can occur up to a year after pollination, whereas, in angiosperms, the fertilization begins very soon after pollination. The shorter time leads to angiosperm plants’ setting seeds sooner and faster than gymnosperms, which is a distinct evolutionary advantage.

Double Fertilization

Double Fertilization is a rule on Angiosperms. This means that the Fertilization in Angiosperms involves the joining of a female gametophyte (megagametophyte, also called the embryo sac) with two male gametes (sperm).