The unit of sexual reproduction is a gamete, which is a haploid reproductive cell with a single set of chromosomes. During sexual reproduction, two gametes, one from each parent, combine into one diploid cell known as a zygote in a process called fertilization. In males, the gamete is called sperm, while in females, it is called an egg or ovum. The resulting offspring is genetically unique and has a combination of traits from both parents. Sexual reproduction is the most common life cycle in multicellular eukaryotes, such as animals, fungi, and plants.