True, when succession occurs after a disaster, like a wild fire, its called secondary succession.
Secondary succession occurs when an existing population has been reduced due to a fire. So that it occurs on soil that was already present prior to the disaster.
In biology, diffusion is the movement of substances with the concentration gradient, which means they move from an area of high concentration to an area of low concentration. Facilitated diffusion is diffusion that is performed with the help of a carrier protein that can move particles of the substance.
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:
