Random fertilization of male and female gametes and crossing over during meiosis adds to the genetic diversity of organisms that reproduces sexually. The progeny of sexually reproducing organisms carry parental combination. Along with this new genetic combination is also carried. Asexual reproduction does not include meiosis and fertilization of male and female gametes that you must be knowing and so a single parent cell is present in reproducing. Therefore, clones are reproduced during asexual reproduction. This is how they differ and so this is your answer.

I hope that's clear.