Question

difference between self pollination and cross pollination

Answer 1

when pollen grains are transferred from anther to stigma of same flower or different flower of same plant then it is self pollination.
when transfer of pollen grains happens in different flower of different plant then it is cross pollination

Answer 2

When pollen grains of anther fall on the stigma of the same flower then it is called as self pollination. And when the pollen grains of one flower fall on the stigma of any other flower then it is called as cross pollination.