To create more genetic variability so as give momentum to the process of evolution.
by insects
the differences between a unisexual and a bisexual flower is unisexual flower- the flower may either contain stamen or a carpel. cross pollination takes place in such kinds bisexual flower - such flowers contain both stamen and carpels . there are chances of cross pollination and self pollination in such flowers.
By specialized insects
Pollination occurs when the pollens from the anther of a flower is transferred to the stigma of the same or another flower. This is of two types- Self-Pollination(when the pollens from the anther of a flower are transferred to the stigma of the same flower or plant) and Cross-Pollination( when it gets transferred to the stigma of flower on another plant). Pollination is brought about by the help of various factors like insects, birds,wind, water.
In cross pollination there is wastage of pollen grains , but in self pollination there is no wastage of pollen grains.
The process of pollination from same flower is called self-pollination. the process of pollination from another flower of same breed is called cross-pollination.
cross and self pollination
Hibiscus plants can be both self-pollinating and cross-pollinating. They are primarily pollinated by bees, butterflies, and hummingbirds, who transfer pollen between flowers as they feed on nectar. Hibiscus flowers can self-pollinate when the pollen from the anther is transferred to the stigma within the same flower.
The two main types of pollination are self (or autogamous) pollination and cross (or heterogamous) pollination. Self pollination - is when pollination is tansfer from the anther to the stigma of the same flower. Cross pollintion - is when pollination is transfer from the anther to the stigma of another flower
The flower is to attract insects and bees, etc, and aid in cross-pollination for seeds to develop. If cross-pollination doesn't take place, there will still be a flower, but no seeds will develop.
Cross-pollination increases variation within a plant species by introducing new genetic material from multiple individuals. This leads to increased genetic diversity and the potential for beneficial traits to emerge through recombination.
self-pollination cross-pollination wind-pollination