B.Sc.2 year notes BOTANY & ZOOLOGY

Who discovered double fertilization? Double fertilization was discovered by Nawaschin in 1898 in liliaceous plants, 

Double Fertilization Definition “Double fertilization is a complex process which involves the fusion of one female gametophyte with two male gametes” What is Double Fertilization? Double fertilization is a chief trait of flowering plants. In the phenomena, one female gamete unites with two male gametes. One of the male gametes fertilizes the egg resulting in the formation of a zygote and the other unites with 2 polar nuclei for the formation of an endosperm. In angiosperms, fertilization results in two structures, namely, zygote and endosperm, hence the name “double fertilization.” Double fertilization is a complex process where out of two sperm cells, one fuses with the egg cell and the other fuses with two polar nuclei which result in a diploid (2n) zygote and a triploid (3n) primary endosperm nucleus (PEN) respectively. Since endosperm is a product of the fusion of three haploid nuclei, it is called triple fusion. Eventually, the primary endosperm nucleus develops into the primary endosperm cell (PEC) and then into the endosperm. The zygote becomes an embryo after numerous cell divisions.