Suggest some advantages and disadvantages of self-pollination to a species of plants.

Hint: Pollination is a mechanism of transferring pollen from the androecium or the male part of a plant to the gynoecium or the female part of a plant. It later results in fertilization and the production of seeds. Most often this process is done by an animal or by the wind or by the water. In some cases, the pollen arrives at the stigma of a flower from the same plant.

Complete answer:
Pollination is a process of transferring pollen grains. In which transfer of pollen takes place from the anther, the male reproductive part of a flower to the stigma, the female reproductive part of a flower.
The carrier or the agency through which transfer of the pollen grains takes place are referred to as pollinating agents. The different types of pollinating agents are organisms such as insects, birds, and bats. External agencies such as water, wind also act as pollinating agents and, in some cases, even plants themselves act as a pollinating agent when pollination takes place within a closed flower. This type of pollination is known as self-pollination.
Self-pollination refers to the transfer of pollen grains from the anthers of a flower to the stigma of the same flower. This type of pollination is commonly found in hermaphrodite or dioecious plants which contain both male and female sexual parts on the same flower. It is less dependent on the external factors to cause pollination. Self-pollination can be classified into two types which are autogamy and geitonogamy.
Self-pollination has several advantages. This process is more sure in bisexual flowers as stamens and carpels mature simultaneously. Self-pollination has indefinite preservation of parental characters. In this type of pollination, pollen grains do not waste. There is no requirement of producing nectar and scent by flowers.
But the self-pollination has some disadvantages also. It has a chance to weaken the variety or the species due to continued self-pollination and also affecting the quality of offspring. Defective characters present in the variety or breed cannot be eliminated in this type of pollination. This process is also unable to yield new varieties.

Note: Pollination is a process of transferring pollen grains from a male part of a plant to a female part of a plant and pollen grains are carried by insects, birds, and bats. Water, wind also carry pollen grains. In bisexual flowers, where both male and female reproductive part is present, the pollen grains arrive at the stigma from the anthers. This type of pollination is known as self-pollination. This process has several advantages as well as disadvantages. While this method is more sure and pollen does not waste but there is no production of the new variety in the self-pollination.