Final answer:
Sexual reproduction involves the combination of haploid sperm and egg cells to form a diploid zygote with 46 chromosomes, which then develops into a new organism through mitosis and cell division.
Step-by-step explanation:
During sexual reproduction, haploid cells from two parents — the sperm and the egg — each carrying 23 chromosomes, fuse to form a zygote. This zygote is diploid, meaning it has two sets of chromosomes, for a total of 46 (23 pairs). The fusion of haploid gametes ensures genetic diversity and the continuation of species while maintaining a stable chromosome number across generations.
Sexual reproduction involves a special type of cell division called meiosis, which reduces the chromosome number by half to produce these haploid gametes. Once fertilization occurs, the zygote begins development through a process of mitosis and cell division, eventually forming a new organism.