In angiosperms, the zygote is diploid while the primary endosperm cell is triploid. Explain.

A zygote is a product of the fusion of a male gamete with the egg cell. Both gamete and egg cell are haploid and result in the formation of diploid zygote.

On the other hand, the endosperm is formed as a result of triple fusion in which one male gamete fuses with the two polar nuclei in the central cell. All three are haploid structures that result in the formation of triploid endosperm.