Answer and Explanation:
All cells including the gametes contain chromosomes. Each gamete cell after cell division contains 23 chromosomes. After fertilization, the diploid number of chromosomes which is 46 is restored in the zygote.
Meiosis, a type of cell division, has two phases which eventually lead to the formation of four daughter cells with equal number of chromosomes. Gametes are haploid in nature and thus meiosis I involves separation of homologous chromosomes hence the reduction in the chromosome number. Meiosis II involves separation of sister chromatids in the daughter cells resulting in four daughter cells with 23 chromosomes.
Meiosis ensures that chromosoe number does not double with each successive generation as the resulting daughter cells are gametes, two of which must fuse to form a zygote.