Answer:
The transfer of mature pollen grain from anther of the flower to the stigma of the same flower of the same [species is called self pollination.
Generally, the transfer of pollen grains by wind,animals,and water to stigmas is called pollination. It is a means of vegetative propagation which ensures reproduction.
Therefore during self pollination, the same genes are distributed from one generation to another. Thus genetic purity is ensured. It also ensured reproductive success. because there is little chance of the pollen grain getting lost in transit. It is also certain a particular plant would always breed true.
Additionally it prevent the process of transfer of genes in some transgenic crops( rice, maize) where through genetic engineering some genes are introduced in their genome.
The only negative effect is lack of genetic diversity. Therefore after a period of time the plants get weak and prone to diseases and infection. Because of poor resistant from lack of variation.
Explanation: