Diploid cells have two copies of each chromosome, usually one from the mother and one from the father. Most somatic cells (body cells) of higher organisms are diploid or polyploid (three or more copies of each chromosome, often found in plants), whereas their reproductive cells are usually haploid (they have only one copy of each chromosome).
When reproducing, haploid sex cells of both parents will generally merge to form a diploid cell, the zygote, with unique genetic properties, which quickly becomes the embryo.
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