So why are angiosperms and their life cycle important? Angiosperms make up 90% of living plant species. The two major characteristics of an angiosperm are the flower and the fruit, which play a critical role in the life cycle of the plant. The flower is necessary for sexual reproduction. The angiosperms rely on pollinators, such as insects, to transfer the pollen from flower to flower. The organs within the flower are the sepals, petals, stamens, and carpels. The bright color of the flower petals are an adaption necessary for attracting pollinators. The fruit is used to protect the seeds and help in dispersing the mature seeds. Some angiosperm fruits are not conventionally recognized as a fruit. In maples and dandelions, the fruits have adapted with propellers or parachutes to enhance the movement of the seeds by wind dispersion.
The angiosperm life cycle appears complex and has many characteristic attributes. The haploid part of the cycle begins with the production of the male and female gametophytes. The male gametophyte has two haploid cells that form the tube cell and two sperm. The female gametophyte consists of an embryo sac that holds the egg. After pollution, the sperm are discharged into the ovule. The fertilization signals that transition from a haploid to a diploid stage of the cycle. Angiosperms have double fertilization, which means that one sperm from the male gametophyte fertilizes the egg and the other sperm fertilization a central cell in the ovary and forms an endosperm, which is the food supply for the seed, while it is dormant within the fruit. The seed develops into the sporophyte, which is diploid. Then the life cycle begins again. The adaptive nature of the angiosperms provides the beauty of spring and the nutrition fruits.