i) Sexual reproduction combines DNA from two individuals (male and female) due to which the offspring has a lot of variations. On the other hand, in asexual reproduction, only the DNA of one individual is copied due to which the variations in the offspring are extremely small.
ii) Due to lot of variations sexual reproduction allow species to change to more advanced forms from one generation to the next and speed up evolution. On the other hand, asexual reproduction does not allow a species to change much from one generations to the next and hence evolution becomes very, very slow.
