What is the relationship between meiosis and sexual reproduction?

In organisms, the process of meiosis, is essentially responsible for the maintenance and formation of the gametes and or sex cells, and the chromosome number for them, it is through this can not only gametes form for the complex multicellular organism, but also if there is no problem, when separating these chromosomes in the gametes, it allows for the formation of gametes with the correct ploidy or chromosome number, which is extremely important in sexual reproduction, as in this process, gametes move and upon undergoing a series of steps, ultimately fertilize producing a zygote of appropriate ploidy. This is from the combination of gametes with the correct number of chromosomes. Usually the resulting zygote is diploid and has 2 sets of chromosomes, each set coming from the respective parent.