Triploid [Pu- + (Poly)Ploi]

A triploid is a polyploid in which each cell contains three complete haploid sets of chromosomes instead of two, like a diploid. Thus, a triploid has 3n chromosomes, where n is the number of chromosomes in the haploid set.

Triploidy is common among plants and some invertebrate animals. In plants, triploids can arise as a result of incorrect cell division during meiosis or fertilization of a haploid cell with a diploid one. Triploid plants are usually larger, with higher productivity than diploid relatives, but are often sterile due to disruption of meiosis during the formation of germ cells. In animals, triploidy is less common, often as a result of errors in egg division. Triploid animals are usually not viable due to a variety of developmental problems.