A haploid cell contains only one complete set of chromosomes, which is half the number found in diploid cells. In humans, for example, haploid cells have 23 chromosomes, while diploid cells have 46. Haploid cells are crucial for sexual reproduction, as they combine during fertilization to form a diploid zygote. In many organisms, including plants and fungi, the haploid stage is a key part of their life cycle. In plants, for instance, the haploid phase is represented by the gametophyte, which produces gametes. These gametes are then involved in the formation of the next generation through fertilization.