When a seed of an orange is squeezed, many embryos instead of one are observed, this is due to polyembryony. Polyembryony is the occurrence of more than one embryo in a seed. This takes place in many Citrus fruits such as orange and mango varieties when some of the nucellar cells surrounding the embryo sac start dividing and protrude into the embryo sac. These cells develop into the embryos and as a result in such species each ovule contains many embryos.