Angiosperms are plants that produce flowers.
Flowers have a stamen with two pollen sacs. The pollen is released from the stamen and fertilizes the female part of the flower. The stamen of the flower is designed to prevent self fertilization of the flower. The pollen is carried from one flower to another by animals like bees or can be blown in the wind. Once the pollen fertilizes the ovary of the flower seeds and fruit are formed.
The formation of fruit helps in the dispersal of seed by animals, wind, water, etc. The fruit, in addition to attracting animals also plays the role of keeping the seed safe. The seed is designed in a manner that facilitates the growth of new plants. There are sufficient nutrients in the seed that allow a young plant to grow without having to extract nutrients from the environment. This provides the plants some time during which they can grow and gain the ability to be able to absorb water and nutrients on their own.
Angiosperms have become the predominant group of plants on land due to the fact that they produce seeds which increase biodiversity and enhance the chances of survival.