Maize (Zea mays) is a diploid organism with 2n=20 chromosomes in somatic cells, meaning the haploid number (n) is 10. The endosperm in angiosperms is typically triploid (3n), formed by the fusion of one sperm nucleus (n) with the diploid central cell (formed by the fusion of two polar nuclei, 2n) of the embryo sac.