The number of species of flowering plants is greater than the number of species in the rest of the plant kingdom combined. What feature(s) are responsible for the enormous success of angiosperms? Explain why.

Angiosperms, also known as flowering plants, have several unique features that distinguish them from other plants. These include flowers, fruits, and the presence of double fertilization. We will discuss each of these features and their role in the success of angiosperms.

Flowers are the reproductive structures of angiosperms, serving to attract pollinators such as insects, birds, and bats. The presence of flowers thus enables angiosperms to reproduce more efficiently than other plants, as pollinators help to transfer pollen from one flower to another, resulting in successful fertilization and the production of seeds. Some reasons why flowers contribute to angiosperms' success are: 1. They have a wide range of attractive colors, shapes, and scents, which helps in attracting different types of pollinators leading to increased chances of fertilization. 2. The ability to produce nectar, which rewards pollinators and ensures they will continue visiting the flowers for nourishment.

Fruits are another major feature of angiosperms. They develop from the ovary of the flower, enclosing and protecting the developing seeds. The presence of fruits is advantageous for several reasons: 1. They aid in seed dispersal, as fruits can be carried long distances by wind, water, or animals, which increases the chances of seeds finding a suitable location for germination and growth. 2. Many fruits are edible and provide nutrition to animals, which, in turn, helps dispense the seeds within the fruits. This mutualistic relationship benefits both the plant and the animal.

Double fertilization is a unique process that occurs only in angiosperms. It involves the fusion of one sperm cell with an egg cell to form a zygote, along with the fusion of a second sperm cell with two polar nuclei to form the endosperm, which serves as a food source for the developing embryo. The endosperm ensures that the developing embryo will have a readily available food source, increasing the chances of successful germination and seedling establishment. In summary, angiosperms exhibit unique characteristics such as flowers, fruits, and double fertilization, which make them more successful than other plants in terms of reproduction, seed dispersal, and germination. These features have led to their enormous success and the greater number of species compared to other members of the plant kingdom.