I think the wording/structure of this sentence is rather misleading and confusing, for the content of the sentence could be misunderstood to read that mitotic cell division allows one-celled zygotes to develop as a result of meiosis, which is not exactly clear nor accurate. Instead, I would rearrange the content in a more realistic series of events so as to simplify it. It would read: Meiotic cell division produces haploid gametes which, upon fertilization, become a diploid zygote. Mitotic cell division allows sexually reproducing organisms to continuously grow and repair its cells.[1] 

  1. ^ Maton, Anthea (1997). Cells: Building Blocks of Life. New Jersey: Prentice Hall. pp. 70–74. ISBN 0-13-423476-6.