Final answer:
Haploid genomes contain a single set of chromosomes, as opposed to diploid cells which contain two sets. For instance, human gametes are haploid with 23 chromosomes, while somatic cells are diploid with 46 chromosomes. During fertilization, two haploid cells merge to form a diploid zygote.
Step-by-step explanation:
Haploid genomes do not contain two sets of chromosomes; rather, they contain a single set. In contrast, diploid cells have two sets of chromosomes (2n). For example, human gametes, which are haploid cells such as sperm or eggs, each carry 23 chromosomes, or one complete set of chromosomes (n). This is half the number found in diploid somatic cells which have 46 chromosomes, two sets of 23 (2n), one set inherited from each parent. During sexual reproduction, two haploid cells (n + n) unite to form a diploid zygote (2n), ensuring the offspring has a complete set of chromosomes.